Inefficient Home Affairs Online System!!

I have to renew my passport. I am in SA for only 6 weeks before I fly back to the UK. My passport expires July next year so I can only do it now. You can no longer do walk ins at branches, you have to make an appointment. I cannot make an appointment as the system is not sending me the OTP to login. I have a UK cell Nr which the home affairs website allows as they have a dropdown menu to choose which country your phone number is from. It is like pulling teeth trying to get anything down with government institutions in this country. But due to the lack of efficiency of the dept of home affairs, I will be the one getting a warning in my British Passport because I will have no choice but to enter SA on it next time I come home due to the SA one having expired.