Reimburse me and then ask the money back a 2 months later

I just received an SMS that I owe Discovery money. This is not correct, and it should have been resolved a long time ago as I reported their mistake to them on various occasions. Including a previous Hello Peter complaint that was supposedly resolved. I paid the service provider then claimed it back from Discovery. Discovery then paid me and the service provider, so they need to recover the money from the service provider. This is the last feedback from the service provider “Discovery Medical Aid contacted our office to advise us that they have made a mistake by making a payment to the practice. We are going to request a reversal claim on this amount from Discovery.” Discovery made the mistake by incorrectly paying the service provider after I already paid them upfront, so they must rectify this. There are serious administrative issues at Discovery Health and I am considering moving over to another medical aid because of it.