When a shipment fails in SKULabs, the error message usually comes directly from the carrier or shipping provider (EasyPost, Shippo, or the carrier itself). This guide covers the most common errors customers run into and exactly what to do to fix them. If you encounter an error not listed here, use the Submit ticket button on the error message to send the full details to our support team.

This is the most frequently reported shipping error in SKULabs. It appears as:

Despite the vague wording, this almost always means one thing: your EasyPost carrier account has been disconnected, expired, or is no longer valid. EasyPost is looking for a carrier account that it can't find.

If you're suddenly seeing this error on many orders at once, it's likely an EasyPost service outage or a mass carrier credential expiry. Check the EasyPost status page to see if there's an active incident. If there is, the issue will resolve once EasyPost restores service — no action needed on your end.

SKULabs is referencing a carrier account ID that no longer exists in your EasyPost account — usually because the carrier was removed from EasyPost directly, or because your EasyPost account was changed.

Fix: Go to Settings > Carriers, delete the affected carrier, and re-add it with current credentials. If you recently switched EasyPost accounts, contact SKULabs support — we'll need to update the carrier account references across your stores.

The FedEx account number saved in SKULabs or EasyPost does not match what FedEx has on file.

See also: How do I add a carrier account through EasyPost?

EasyPost could not validate your DHL account number when attempting to purchase a label.

UPS updated their API authentication to OAuth in 2023. If you're seeing UPS authentication errors, your account credentials may need to be re-authorized using the new workflow.

Follow the steps in UPS new OAuth workflow to reconnect your UPS account.

The USPS carrier account connected through Shippo has been deactivated — usually because of inactivity or a change in Shippo's USPS account management.

Fix: Go to Settings > Carriers and reconnect your Shippo USPS carrier. You may need to log in to your Shippo account and reactivate the USPS connection there first.

The carrier returned no available shipping options for the order. This usually means something about the order, package, or carrier configuration is preventing rates from being generated.

A general EasyPost error with several possible causes — most commonly an issue with the destination address, package dimensions, or a carrier-specific restriction.

See also: EasyPost: Unable to complete shipment purchase

Your EasyPost account balance has run out. SKULabs purchases labels through your EasyPost account, so if the balance is zero, label purchases will fail.

See also: EasyPost Insufficient Funds Error

EasyPost has blocked this shipment for an account-level reason — usually a billing issue, account suspension, or a carrier-specific restriction on your EasyPost account.

Fix: Contact EasyPost support directly at support@easypost.com. SKULabs cannot resolve account-level EasyPost issues on your behalf.

The carrier account linked to this order or store no longer exists in EasyPost, or has been disabled.

Fix: Go to Settings > Carriers, remove the affected carrier, and re-add it with current credentials.

A timeout occurred between EasyPost and the carrier's API. This is a temporary issue.

Fix: Retry the shipment. If the error persists, check the carrier's API status or try a different service level.

EasyPost is experiencing a service outage or maintenance window.

Fix: Check status.easypost.com for active incidents. Wait for the outage to resolve and retry. No changes needed in SKULabs.

A reference number field is populated for a UPS service type that doesn't support reference numbers (such as certain residential or SurePost services).

SKULabs cannot determine which warehouse to ship from — usually because no default origin warehouse has been set for the store.

See also: Advanced shipping configuration

FedEx requires a phone number on the recipient address for certain service levels.

Fix: Open the order, click Edit address, and add a phone number. If this happens frequently for orders from a specific channel, check if the channel is configured to import phone numbers.

FedEx requires a commercial invoice for international shipments. The customs form is missing or incomplete.

Fix: Open the order, click Customs or Commercial Invoice, and fill out the required customs information (contents description, declared value, country of origin, HS codes). Then retry.

The destination country is not supported by FedEx for the selected service level, or your FedEx account is not enabled for international shipments to that country.

Fix: Try a different FedEx service level, or contact FedEx to confirm your account's international eligibility. You may need to use a different carrier for that destination.

FedEx requires a 2-letter state/province code (e.g. "CA" not "California").

Fix: Open the order, click Edit address, and change the state field to the 2-letter abbreviation.

The customs form has too many line items for FedEx's international API.

Fix: Consolidate commodities on the customs form by grouping similar items. Contact SKULabs support if you need help adjusting the customs form.

FedEx does not deliver to PO Box addresses.

Fix: Contact the customer for a physical street address, or switch to USPS which supports PO Box delivery.

Your FedEx account is attempting to file Electronic Export Information (EEI) with an invalid AES citation. Applies to exports over $2,500 or exports requiring a license.

Fix: Contact your freight broker or FedEx representative for a valid AES citation or FTR exemption code, then enter it in the customs form on the order.

UPS does not offer the selected service level between your origin and the destination.

Fix: Click Rates on the order to see what UPS services are available. Select a different service level, or switch to a carrier that serves the destination.

Your store's ship-from address is missing a zip/postal code.

Fix: Go to Settings > Stores, click the edit icon, and make sure the origin address has a complete postal code.

A temporary UPS API issue, not a problem with your order or settings.

Fix: Wait a few minutes and try again. If it persists, contact SKULabs support.

This is a UPS warning, not an error — the shipment will still process. UPS is flagging that the actual billed rate may differ from the quoted rate (common with negotiated accounts). No action required.

Your UPS account number in SKULabs doesn't match what UPS has on file.

Fix: Go to Settings > Carriers, find your UPS carrier, verify and re-enter the account number.

The destination postal code doesn't match the province on the order.

Fix: Open the order, click Edit address, and correct the postal code or province so they match.

The declared customs weight exceeds the maximum for the selected Canada Post service.

Fix: Reduce the declared weight on the customs form, or select a Canada Post service that supports heavier packages.

Your Canada Post account billing configuration is not compatible with the selected payment method in EasyPost.

Fix: Contact SKULabs support. This usually requires updating the billing method on your EasyPost Canada Post carrier account.

The order is shipping internationally and no customs information has been filled out.

Fix: Open the order and click Customs to fill out the customs form with contents description, value, country of origin, and quantity.

The postal code and city name on the order's shipping address don't correspond to each other.

Fix: Open the order, click Edit address, and correct either the city or postal code.

The address type doesn't match what the carrier expects.

Fix: Open the order, click Edit address, and change the Address Type to the correct classification (Business or Residential).

The order has a malformed or missing email address, which some carriers require.

Fix: Open the order and check the customer email field. Add a valid email address and retry.

A required field is either missing or too long for the carrier's API. Common culprits are long company names or address lines.

Fix: Open the order and review the shipping address fields for anything blank or unusually long.

APO and FPO addresses are U.S. military addresses that can only be shipped via USPS. Attempting to ship to an APO/FPO address with FedEx, UPS, or DHL will always fail.

Fix: Switch the carrier to USPS for any order with an APO, FPO, or DPO destination address. You can automate this with a shipping rule — see How to create and use shipping rules.

Labels can only be voided before they are scanned by the carrier. Once a package has been picked up or scanned, it is no longer eligible for a void through SKULabs.

The shipping service isn't available for this specific package — usually due to weight, dimensions, destination, or account restrictions.

Fix: Click Rates on the order to see which services are actually available. If you believe the service should be available, contact the carrier directly to verify your account eligibility.

The carrier account used for return labels hasn't been added to your EasyPost account, or was entered incorrectly.

See also: How to automatically print a return label to include in the box

Shippo encountered a temporary error communicating with the carrier.

Fix: Retry the shipment. If it fails repeatedly, contact Shippo support at support@goshippo.com or check status.goshippo.com.