Summary
If the bank account you wanted to connect is closed, Konfir can't access it. You'll need to verify the relevant period through another source.
Do you have another open account?
If you have another active bank account - at the same bank or a different one - connect that instead. If income was deposited into it during the period being checked, it may be all you need.
If the account is very new and doesn't have much history, connect it anyway. Your verifier can see what's available and decide whether additional evidence is needed.
Other ways to verify
If you don't have a suitable open bank account, skip the Open Banking data source and continue with your other available data sources - you can still submit your verification.