Product: Checking or savings account

Had a {$1700.00} mortgage payment drafted on XX/XX/XXXX as intended. I made a deposit on the same day, but it wasn't credited until the next business day and my mortgage payment was returned for insufficient funds. That was all done correctly and I have no argument. Both my mortgage and account are with the same bank ( BMO Harris ). On XX/XX/XXXX I made a manual mortgage payment through their app/online, but it was Veteran 's Day, a Federal holiday and didn't post until XX/XX/XXXX. On XX/XX/XXXX, the mortgage servicer also auto-drafted my account in a second attempt for payment, but with XXXX going through on the same day it overdrafted my account. There were sufficient funds for XXXX payment, not XXXX. I called the bank on XX/XX/XXXX and was promised that it would be corrected with XXXX of the XXXX {$1700.00} payments being returned by the next day on XX/XX/XXXX. That didn't occur so I called again on Friday XX/XX/XXXX and was transferred to the mortgage servicing department, which couldn't see my bank account information even though with the same bank. I was told they had posted XXXX payments so I wasn't due until XXXX, so I asked for XXXX to be returned since that wasn't the intention at all. XXXX said would take XXXX business days to have the payment returned or if I could send them a bank statement showing sufficient funds for both payments to clear my account and it would take XXXX business days. The second payment overdrafted my account so that wasn't possible. I called the bank back and talked to the deposit side, XXXX, who told me she understood the problem and could do a manual reversal since it really should have bounced back the next day ( XX/XX/XXXX ) and didn't. Unfortunately it was a Friday so she said it probably wouldn't post until Monday. Nothing changed on Monday XX/XX/XXXX and my account was still showing overdrawn. I called back XXXX different times on Tuesday the XXXX, speaking to XXXX different people, multiple times with all of the call and hold times totaling more than XXXX hours. The best answers I received from a Resolutions Team manager was XXXX ) The people I spoke to the week before didn't do it correctly XXXX ) She had now sent the emails to the correct team and people and there was nothing I did wrong ( implied the prior customer service people did it incorrectly ) and XXXX ) the bank side should have pulled the funds back on XX/XX/XXXX due to insufficient funds but it was too late now and they needed the mortgage servicing side to refund them. However, now that it was being processed correctly it would take XXXX business days to complete and Tuesday XX/XX/XXXX was not day XXXX, Wednesday XX/XX/XXXX would be day XXXX resulting in this issue of my account showing insufficient funds lasting from XX/XX/XXXX until as long as XX/XX/XXXX. I spoke with the mortgage servicing department who refused to refund anything due to their process even now that they had the information needed to do so. The deposit side of the bank said it was too late to pull the funds back, had to wait on mortgage servicing and there was no one with the authority to do anything differently. At best she could escalate it by email to someone that may be able to resolve it in XXXX " or so '' business days. This was on XX/XX/XXXX a full XXXX calendar days and XXXX business days after the issue caused my account to be overdrawn. I was told that since my mortgage and deposit account were with the same bank ( even though the XXXX couldn't talk or see the transactions of each ), that was why it was allowed to stay overdrawn and nothing was returned.