Complete idiots!

I made payment arrange arrangements with Groote Schuur Hospital to pay off my account. 5 months ago Vericred contacted me & said the account was handed over to them & I must pay them rather. I was dubious so phoned accounts department at Groote Schuur & they told me it was not handed it over as I had made payment arrangements with them. Every month, sometimes twice in one day, Vericred phones me. I ask them to check their "recordings" they say they have wherein I have asked for a supervisor & sent emails of all my GSH payments. Today I was phone twice & the 2nd guy put the phone down on me because I got irritated & told him I know he's just doing his job but that he must please get the supervisor to phone accounts department at GSH to sort out. He put the phone down on me. They are incredibly uncooperative & totally useless. I have never dealt with such a bunch of idiots in all my life. Can they not pick up the phone & confirm with GSH? Like seriously what planet of incompetence are the from?