Pathetic accounts department

Good Day I am totally ****ed off with your accounts department. I did receive an email in April stating my account was in arrears.When I checked on my bank statement I've noticed that I did make two payments into my sons account .(This account is closed ).I've contacted the account departement and explained to them what happened.They said I need to send an email with the proof of payments and also a letter from my sons stating that the funds must be transferred.This has been done on the 16/04/2019 On the 21/04/2019 I did receive an email back from Edgars sating they are busy investigating and must allow 14 working days.Guess what NOTHING has been done and now I am getting phone calls and emails from your collections department .Is it to much to ask just to do a note on my account stating what happened and it is under investigation.This morning when I called account your staff member put the phone down in my ears .So please tell me what must I do more