Manual payment ( Internet Transfer) no where to be found.

I am struggling with my monthly payments to Cellc. I have just been on call with them and nobody in thier customer care centre is taking my calls. This is my story: On the 27th of June 2022 Cellc debited my account with an amount of R248.98 this was correct. On the 26th of July they debited my account with an amount of R248.98, this was also fine. In August I didn't pay because I had asked them to change my debit order date to the 1st, or 2nd or the 4th of each month the reason for this is that I no longer could afford the 26th because my only income is the my social grant. Sassa. I made an arrangement with them that they should move the debit to the Sassa Dates. They refused saying I should pay them manually via an internet transfer from my Capitec bank account to their Nedbank account. They gave me the Nedbank account details. They further said I would incurred some penalty because of the date change. I obliged and they said I should pay R383.90. This payment was made accordingly. I made it on the 3rd of September 2022. Over and above, I made an agreement with them stating that the next debit order will be in October the 2nd. ( This is the October date for the Sassa grant) Yesterday I send them a Gmail, the reason being that I wanted to make sure that my next debit order will be the 2nd or the 3rd of October. Some lady responded to me via a telephone call thereafter she said she would transfer me to the customer care center. Nobody took my call hence this review. The other issue is that till today Cellc says they did not receive the R383.90 that I paid via internet transfer from my bank account. How can that be. They are the ones who gave me thier Nedbank account and said I could pay them in this method. I have send them the screen short of the payment but till today nobody acknowledges receipt. This transfer was done on the 3rd and today the date is the 28th and nobody can account for it. Can Cellc please do thiet jobs professionally and come back to me urgently please.