SUSPENDED MTN ACC THAT WAS, PAID ON 25 MARCH 2020

I have paid my mtn contracts on 25 March 2020, just to receive an SMS this morning 30 March 2020, on my BIRTHDAY..... stating: Y'ello. We've had to suspend your ability to make outgoing calls due to non-payment of your MTN account. Please pay R 258.17 with MYMTN app or via ABSA, FNB or Standard Bank. Select MTN and use N*** or *** as your payment reference. I have send them an email but no response as in yet even tried to phone them but NO LUCK.. What am I to do please?