Late Mothers Std Bank Account

My mom passed away in Feb. I am executor to the estate but living in CT and Master of the Court in PE. Mom had no money in her account but they wont let me close it until I have a letter of executorship which is proving impossible during Covid and having to rely on someone else to lodge the documents for me. But Standard Bank continues to charge mom bank fees which I eventually accepted but now they are charging OVERDRAFT fees on the accumulating fees and say they cannot do anything without my letter of executorship. That is ******** as far as I am concerned and surely there is someone at Standard Bank who has the authority to look at the situation and waive the Overdraft fee!!!! Apparently not!!! So I thought I would circumvent the situation and pay in the amount owing to stop the overdraft fee but lo and behold they have managed to freeze the account enough for me not to be able to do that but not enough for them not to exploit my late moms account by charging bank and overdraft fees. I am totally astonished at the by the hypocrisy of the system.