Unable to install from Live App Testing invitation

I have received a Live App Testing invitation I sent to myself, and when I try to download it, I get:
“We could not complete your order due to a payment issue. App purchase is now in pending status and cannot proceed to download.”
When I click the link to pending orders, I get a page not found error.
I have recently set up a credit card on this test account, and have not ordered anything, so there are no pending orders. I have set the card to be the default payment method for the account. Is there anything else I need to do? Any way to figure out what’s wrong?
The app is free, and I was able to install a Live App Testing version with no credit card on my account previously.

Hello,

Thanks for posting. Please note that even though Live App Testing is free of charge, the app purchase process is through the Amazon retail page, which means you will need valid payment information to purchase the LAT app.

According to the error message, it seems that your retail account has some issues. Please reach out to the Amazon Customer Service team for further assistance: Help & Contact Us - Amazon Customer Service

Thank you. As far as I can tell, I do have valid payment information. I tried installing a normal free app from the appstore, and it went through with no problem. The problem only seems to happen in Live App Testing. I’ll see if Customer Service can find anything wrong, but I’m not sure they’ll be able to help if the problem doesn’t happen with non-test apps.

I rebuilt my app and started a new test with the new binary, and this time it worked. So either there was a problem with the account that got resolved without any action from me, or there was some intermittent issue with LAT.

Hi, Emma,

I uploaded a new binary for the next phase of my testing, and the issue came back. It only affects apps in Live App Testing (ordinary apps can be installed), so it seems unlikely that it’s a retail account issue Amazon Customer Service will be able to solve, though I can try.