No response on email since November branch nor call centre can help

I have been making payments into the Nedbank credit card account with the wrong reference for more than a year

I got calls saying I didn't pay but sent all the proof of payments.

I went to Nedbank branch they emailed the call centre November last year no one has gotten back. I went to the branch again today they couldn't help find the payments and asked me to call the call centre.

Call centre didn't want to take the details that I have been paying into as they said my account is handed over I need to speak to the collection people. The more I tried explaining the money is was not paid into my credit card it's into nedbanks account they wouldn't even look.