Dissappointed!

I have been a Cell C for 18 years. My account was in arrears and I made a payment arrangement with Cell C on the 19th of February to bring the account up to date (payment was promised for the 2nd of March). On on Sunday at 19:00 I received an SMS from cell C stating "Your cancellation request was processed successfully and the contract will be terminated on 28/02/2021" My phone lines are deleted on the network. Full payment was made on the 1st of March (as promised) and emailed through to Cell C. The payment is reflecting on my account but "NOTHING"can be done.