USAA complaint: Lost Check Deposit

I recently mailed a deposit to USAA because it exceeded the allowable limit through the phone application. I called USAA to determine how to deposit a check. USAA told me that I needed a special deposit ticket which they sent. After waiting for over a week and a half, I did not receive the deposit slip. I called USAA again to find out what to do. I was told to use FEDEX to expedite the check to the San Antonio Office at 10750 McDermott Fwy with a regular deposit slip. On 15 December I sent the check to USAA via FEDEX. On 19 DEC I received a notification from FEDEX that the check was delivered at 9:10 am. Later in the afternoon, I called USAA to verify they had secured the check. USAA told me that they received the FEDEX package but could not tell me where the check was at. USAA informed me that they process the checks within 24 hours. The afternoon of 20 DEC, I called USAA to verify whether or not they secure the check but no one could tell me where the check was at. I am extremely concerned that USAA is not adequately accounting for financial documents or resource through their mail in deposit section. We are simply requesting that USAA acknowledge they’ve secured our check.