The only thing I could find in MMB (for a flight to USA) was a downloadable attestation form, so yesterday we used the salesforce link posted here to upload our covid docs.

Today, we got a message from BA to say that our docs had been verified, and that we would be able to check in online or in the app. Seven minutes later, we both got further emails to say that they were unable to verify our documents and that we would have to check in at the airport. It also says that there is not enough time to repeat the verification process, although the trip is still 7 days away. How can this be so difficult?