Terrible service from Fnb connect

I make use of many services with Fnb including Banking

business banking, Insurance and Fnb connect. I have had serious issues with my Fnb sim card ever since upgrading to a better package, I have called Fnb to discuss this with them more than 30 times now only to hear that they will fix the issue immediately. only to find that it never gets resolved I then started to deal with the floor managers who assured me that they would deal with this on personal level and be sure to return my phone calls...... I have never heard from anyone and now wanting to cancel all the services I have with Fnb for the appalling service I have received.