This service issue appears when your next bill is posted by your service provider before your 2nd Flex payment for the previous bill has been completed.
While your previous bill has already been paid to your service provider in full, there’s still an outstanding balance on your Flex account until your 2nd payment to Flex is made. Until that balance is resolved, Flex can’t process a new bill.
When this happens, you’ll see a message in the app letting you know that your new bill can’t be paid yet.