Like others here, I closed my BOA account long ago.
I would suggest threatening them with closing your account unless they refund your money. Then, whether they give you your money or not, close the account within the next two months. Use that time to find a good local bank to move to, and check references with friends so you know it’s a good one.
I started with a Credit Union a long time ago. It did not pay its tellers very well thus it functioned as a teller training school for the local banks and richer CUs and some of them made errors from time to time but they were always resolved satisfactorily without calling for attorneys and I love that my account, which was necessarily normally below $200 back in the day didn’t dribble away with the constant nickel and dime fees charged by the banks I had dealt with previously. That factor alone kept me at the CU. There have been no mistakes in the last 8 or 9 years and there are still no fees. They didn’t lose any money in the late real estate meltdown and hold all the mortgages that hey originate in their own hands. They don’t sell them. I like that in a bank or CU.