Unfair service from Truworths

I don't believe what Truworths did to me, I have paid my account in time and even sent a proof of payment done follow ups to check if it was received but no one helped, can Truworths stop being useless,do your job and fix my credit otherwise I will take this far Is this how you should treat your customers? Is not fair at all because now you have the nerve to call and send smses that my paid account is overdue.