Unprofessional and unreasonably long waiting time for responses on simple returns

I am so annoyed by how long Discovery Vitality is taking to give me a simple authorisation letter for a return I made on 15 Feb 2025 using my Nike benefit. I have been asked for multiple things to complete the letter yet still no letter has been sent. Discovery Vitality if you just want to make money from me and not do the return then just say so instead of being unprofessional and dragging this out. I have been patient enough with your ridiculous requests like asking for a slip for an online transaction and your agent who seems to only know how to call after 4.30pm when the day is over to ask for things for the letter.