Paid up Letter

I made payment on my CellC account after being contacted by their collection Shapiro Shaik Defries. Once payment was done and POP sent to the requested parties. I have yet to get a response regarding a paid up letter and proof/confirmation that the amount is closed. When I call SSD they refer me to CellC. I get verbal confirmation from both parties that the account is settled and closed, however no e-mail communication, Ref #s ,***, ***,***. Now I am unable to get through to and agent at CellC as they're voice prompts state that the number I enter is not a CellC number. Please help resolve this issue as I have been requesting this documentation for 3 months! Contact me via e-mail - ***