Status 400 is returned both when the buyer's Access Point rejects an invoice and when tax reporting fails. Check SCIGovtStatusCode to tell them apart, then follow the matching steps.

SCICloudStatusCode 400 covers two scenarios. Check SCIGovtStatusCode to identify which one applies.

Network delivery rejection (MLR RE)

The buyer's Access Point rejected the invoice for a content or routing error. The rejection reason appears in the notification's StatusReason field.

Steps:

1. Review the rejection reason. If it's a content error, correct the invoice data and submit a new invoice with a new invoice number.

2. If it's a routing error (participant registered but endpoint rejected the document), contact the buyer to confirm their Access Point is correctly configured.

3. Don't reuse the original invoice number for a corrected submission.

TDD reporting failure (eMLR RE)

Unimaze reported the TDD to the Slovak FA, but the report was rejected. The error details appear in StatusReason.

Steps:

1. Review the error. TDD rejection typically indicates a data problem in the invoice that passed network delivery but failed the Slovak FA's reporting validation.

2. Contact Sovos support. TDD failures may require Unimaze involvement.