Fnb connect simcard not receiving sms's and calls

I use fnb connect simcard. I no longer receive sms messages and incoming calls. I called to complain. They gave me a case number and they asked for any form of communication since my phone couldn't receive calls. I gave them my email address and my spouse's contact number. No response from them until I called them again. I was assured that they will come back to me. They later responded through an email saying they have refreshed my simcard and I should restart it, in case the problem persists, I should let them know. I did restart, but still no messages and incoming calls. I called fnb again, I was promised they will come back to me, I'm still waiting. I feel my account is not safe since I won't be able to realise whatever is happening to my account since there's no notification to alert me of any transaction taking place. I deeply feel that there's a foul play taking place. I had to shift my money to another bank for its safety and I'm expecting a deposit soon into my account. I'm worried. Are we safe with fnb? I don't think so, even their service to customers dictates.