Unprofessional

I made an arrangement to settle an account that was handed over to them. I finished paying up last week and now l am struggling to get a paid up letter! I can't deal. I was told that l would have the letter by latest this past Tuesday and that never happened. I have been then calling and emailing Mbalenhle whom l was communicating with. She is no longer responding to my emails. Such bad service I'm not happy at all.