Product: Credit card

I have a balance on my credit card with First Tech and a check was issued to First Tech on XX/XX/XXXX to pay off my credit card account balance in full. My credit card payment date was approaching and the payment hadn't cleared so after following up with the bank that issued the payoff check I received confirmation that the check to First Tech was received and deposited on XX/XX/XXXX. On XX/XX/XXXX then called First Tech and asked why the payment which is showing up as cashed, hasn't been applied to my account. The representative said she couldn't locate the check that was made, i provided the check number and amount and they still couldn't locate it so they said they would call me back, i offered to email them the confirmation I received from the other bank. I received a message later that day saying that they couldn't locate the account to apply the payment with the account numbers provided on the check to so they sent a certified check to the address on file on XX/XX/XXXX. I called First Tech again on XX/XX/XXXX to follow up on this. I asked why they couldn't find the account, the check provided the first 5 digits of the account and the last 4. They said they need the full account number. I then asked where the check was mailed to and was told that is was mailed to MY address on file. I asked how is it that they knew to direct that check to me and my address but they still couldnt find the account associated. I received no reponse. I asked if they are sure the check will be mailed to my address on file, they assured me that it will. Given that they cashed the payment but didn't apply it to my account I asked if they could put a stop payment on the outgoing check, they said it couldn't be done. I asked if I could have a payment extension, payment is due in 3 days since this was First Tech 's error in applying the payment, they said no. I was told the only thing I can do is to wait for the check to be sent to me and ask my other bank to issue another balance transfer check with the full acct number. I told them that I couldn't make the minimum payment in 3 days, but i can pay it late. Asked if they could waive it as a late payment and not report it as late to the credit bureaus since this is an error on their side. They refused and said a late payment is a late payment. I don't feel that First Tech is being truthful about not being able to locate my account and thus apply the payment and that they are being unreasonable/unfair in honoring my request for accepting a late payment with no fees or negative remarks to credit bureaus. I don't believe that they knew to send the check to me but couldn't find my account, especially given that in the balance transfer checks that First Tech issues, they also ommit the full account number. The First Tech representative on the phone told me that it needs to be the full acct number and that first tech always puts the full account number in their balance transfer checks which I have evidence to the contrary ( see attached image of outgoing First Tech balance transfer as proof ). I requested a balance transfer from First Tech in XX/XX/XXXX to XXXX XXXX XXXX, XXXX XXXX XXXX sent back the check with an acct number format consistent with what first tech received. So that is a lie and hypocritical of them. I also asked if First Tech called the number on the check to inquire about the account number/holder to pay off the balance, the person told me that he's not sure that it's part of the payment processing center 's protocol to do that. If they didn't call the number to try to track down my account, i again feel that this was First Tech 's error. First tech 's balance transfer check 's similarly request the check recipient to call the number with any questions so again hypocritical for them to refuse to do something they ask of others.