Blocked Estate late account

I lost my husband on the 1st of September 2023. Opened an estate late account with FNB Polokwane branch on the 26 of October 2023. My late husband did not choose any beneficiaries on all his policies so all the claims were paid into the estate late account including the money that was meant for my children's education. I am the sole signatory on the estate late account and I can access the account via internet banking. The problem started when I tried to transfer the money that is in the estate account into my own account. The account is blocked. Money can go in but I can't take it out. I've been to the branch more than 5 times and the answer I get is, " we are still investigating". I am the only legal wife to my late husband and even got the letter of executorship from Master of the high court. My second born is a university student and my last born is in high school staying at hostel. I took loans to bury my husband and still owing most of the service providers that assisted me during that time. I stay 130km away from Polokwane. My kids might not be able to return to school after the holidays since I can't afford to pay for their fees and traveling expenses. I do not understand the reason why has FNB put a block on this account. The past six months have been very difficult for me 😭 please release the account so my kids can have something on the table and be able to go to school