Yeah, not being clear about what the problem is definitely needs improvement. Have you only created the backup, or did you also verify that it works?
When you select the account on the accounts tab, you should get a "verify backup" option in the menu.
Thanks! That was it. I verified all accounts and the warning button disappeared.
So the problem is that the button does the wrong thing. It creates another backup, rather than offering to verify, particularly if the user has just created a fresh backup. Perhaps there is also another problem, because there should be an "unverified" warning with each unverified account, but I had none of these warnings on any of my several single-address accounts.
Another point to think about is that the backup contains a number of account QR codes and one password. Verifying could be made much easier if the user could enter the password once and scan the QR codes in quick succession. Instead I had to scan one account QR code, enter the password, scan the next, enter the same password again, scan the next, enter the same password again, etc. The clipboard helps, but it still increases the risk of the password being snatched by malware or by somebody peeping at my phone.