Redstone Credit Union review: Payment not accepted

On sunday 2/20/22 I tried to make a payment via phone, to Redstone Credit Union... This was the due date... After putting all the info needed to process this payment, I normally get a confirmation number. This time, I got a recording that I had to wait for the next available rep.. I waited 25 min. nobody responded... I tried again, putting all the info needed to process payment, no confirmation number, just being transferred to next agent.. waited 10 more minutes, system said very high volume of calls, no response. On monday did the same routine, the response was extremley high cal volume... On tuesday, tried again, after 15 minutes, agent came on line.. I explained situation and she said I was going to be charged extra... this is unacceptabe. I should have been able to pay on the due date of 2/20/22, get confirmation number, and hand up...