Paid up letter

I was working for edcon and when i left them they transferd my staff account to an normal account and then i was handed over, i paid the full amount last month the 15th and phoned them the 17th for a paid up letter and they told me 24hours and never got one.. I gave them bad review after 2 weeks and they phoned me again and told me that there was no record of my email there or something send to me.. I gave them 2 email addresses again for paid up letter and the person told me i must wait 24hours again, and tuesday again i asked them for one for the 3rd time.. How can an email take 24hours to send to a person.. I just want an paid up letter thats all and u have to wait almost a month and nobody comes bavk to a person.. What kind of service is this..