POOR SERVICE

Since I've upgraded 10/11/2020 - I don't receive my full package recharge of MTN Mega Talk S and I can't phone out to other networks - even tho the package states that I receive 120 Mtn to Mtn and 120 Mtn to any network?? It keeps saying I must load airtime to continue with the call. I'm a customer since 1989 and this is the first time i receive very poor service from you and I consider to move to another network because of this.