Mtn
Left holding for over 4 minutes and call gets cut

I called earlier as for the past week I have not been able to send any SMS's.
It reads "Operator determined barring", I called spoke to a gent and he gave me the code #330*0000# and said to dial the call button, after that to switch off my phone and on again, should the error persist to call again.
I called again and spoke to a lady who said she will just check what is going on, I did not hear any holding music and sounded like I was placed on mute, after calling out "Hello" twice I did not hear anything and after 4 minutes the call is cut.
I have been having end less issues with MTN and the network I just want to be able to send SMS.
Please check what is the issue in why I can't send SMS's.