Paid but still no Internet

I paid for my internet on the 31st of July but till this day I have no internet, Its so frustrating that no one on the WhatsApp channel gets back to you, I tried email and they only responded after three days , I submitted everything they requested and also on email they only respond the day after, so please do not expect to be assisted immediately. I still do not have internet after they said they see my payment and would like my routers serial number to activate it, I sent them the serial number but I am still waiting. This is the worst ISP I have ever had