Why is the line still in active after payment was made on 24/1??

Account suspended. *** belongs to my sister JSA Jansen van Vuuren but because she is mentally not capable of handling her account I have been paying it for I think the last 5 years. I had a scheduled payment of R100 going off on the 3rd of each month because over the years I worked out an average and it was enough. I moved about 3 years ago and did not change the address for the actual account to my current address and somewhere along the line she went wild with the account. on 24/01 I received a sms saying the account was in arrears with R496.59 and if I pay within 7 days the line would be reactivated. I on the same day paid the amount but the reference I got from the debt collectors did not work so I used the one I always used. I was given a cell number to sent the proof of payment to which I did. For I think about another 6 weeks i got some more messages from the debt collectors but after confirming again payment was made on the 24th January it stopped. The line is still in active. Were do we go from here. I did not stop payment I even increased it to R150 instead of R100 since I do not get any paperwork anymore. My problem is she stays in Mpumalanga and I stay in Cape Town. It went off for the last 52 months every 3rd of the month. About 3 years ago at the end of the year there use to be enough credit for at least one month then I would skip December and start paying again the R100 on the 3rd of January but payment was going off my account for the last 52 months. Just want to know why the line has not been activated after payment was done and I also would like to know if I can at least have a sms with the amount for the month being sent to my phone @ ***. I also pay her accommodation and electricity account and TV licence. All of those accounts are being sent via email and sms to my number. I need to pay R65 to investigate (refundable) but I do not want to go that way since due to lockdown I did not earn any income for the last 2 months.