Product: Checking or savings account

I am reaching out on a situation that is ongoing since XX/XX/22. I have called Huntington Bank 's customer service line multiple times in regard to this with no resolution or answers. I need some kind of idea what my account is under investigation for. I deposited a check for {$3000.00} that I received from XXXX XXXX XXXX XXXX for an XXXX XXXX XXXX XXXX  on XX/XX/22. I attempted to deposit it on the mobile app and it denied it due to it being over the amount I was allowed to deposit for the day. So the next morning I took it into the branch at XXXX XXXX XXXX XXXX, XXXXXXXX XXXX XXXX and spoke to a teller named XXXX. I explained I attempted the mobile deposit, it failed and I would like to deposit it in branch with her if possible. She stated she was a new employee and had to double check with the manager. She did and the manager approved the deposit. I was given a receipt. The following day I attempted to login to my app for online banking and was denied access, I attempted to change my password and it stated an error occurred. I called into the customer service line and was told that the check is being held for processing until XX/XX/22 and that would also lock my online banking access. As inconvenient as that is I understood as it is normal for banks to hold a large check to confirm funds before posting to the account. On XX/XX/22 I received an email from Huntington Bank stating my deposit had been released and my current balance was {$3000.00} as of XX/XX/22. The days following I still was not able to access my online banking so I kept waiting and trying hoping it would release and I didnt not use my card the days following either as my plan was to save that {$3000.00} for the time being. I called customer service on XX/XX/22 to discuss the fact that my online banking was still showing as locked, the representative told me I needed to visit a branch and present my ID to have it unlocked and I asked her if I was going to be able to use my debit card as I was heading to XXXX to make some XXXX purchases. She assured me more than once that I could use my card ; it declined at the register. The following day I entered the same branch I deposited the check at initially and inquired about my online banking and the card being declined to which the same teller, XXXX informed me that my account was under investigation for fraud, no funds were available, and my card had been revoked. After repeatedly demanding an explanation I was told to leave the branch by the manager there stating we cant help you here. I immediately called customer service and have spoken to several people over the last few days to which I am being told I can not get a status on my investigation nor can I speak to the fraud department regarding this. One representative even told me they didnt see where the funds were ever available. I spoke to one Customer Service Supervisor, XXXX, and she stated that it appears they have been attempting to " email the insurance company to verify funds, and haven't received a response back. '' I have spoken with the insurance company who issued me the check and they show it as cashed and have not been contacted regarding the check. I am needing to find out exactly what this " investigation '' on my account is for as they have taken back ALL of my available funds, not just the {$3000.00} for the check they claim is under investigation. I need to be returned the {$3000.00} that my bank showed as a balance on XX/XX/22 immediately. ( NOTE : I selected paperless statements and can not access my online banking statements since I am locked out of my online banking access to view my full account number. ) Thank you.