I'm fed up with Truworths dishonesty and harrassment

I'm really fed up with Truworths dishonesty and harrassment. They never bothered to send me the details to effect a payment on my account during lockdown instead they kept on sending me messages reminding me of payment. As a loyal customer I took great pains trying on the method to pay them as I always do on the 15th of each month until I discovered that they do appear on my banking app and I effected the payment on 15th April online. Ever since then,I'm receiving messages at least twice a day about my account being in arrears.On 17th May,I made a bank statement,went to the local branch to show them proof of payment and I made a payment for this month. I talked to a guy called Sifiso,he made copies of the bank statement and my ID and emailed them to their head office. On the 18th he called me and told me the feedback from the head office that I must wait for 7days while they work on my account. This morning I received a call from the debt collectors saying I'm owing Truworths April and May installments.Once I finish the account payments I will tear their card into pieces and forget about them,they are really disgusting. They can't fix their technical errors and they end up harassing clients