Capitec withholding my late mothers money

I do not know if I'm contacting the right place but I hope I will find some assistance. Capitec bank won't release my late mothers funds and it has been more than 2 months now. When we complained they moved the money to a new savings account that we don't have access to. The money was in an account that we could view, we opened an estate account with FNB in March and they told us that they had to investigate the legitimacy of the letter of executorship before the account could be opened. That process took about 2 hours, capitec said the same thing but now it has been more than 2 months and I have even contacted them on Facebook, that's when they moved the money to a different account that is not the estate account we provided them with.

I hope you can assist me with this because we do not know what to do now, it's like the bank is purposely withholding these funds and the more they're keeping the money with them, our bills are piling up.

Miss N.R. Mnguni.