Colmed not paying the Service Provider

I had a dental appointment at Valleyview Heathworx and had a payment arrangement. Due to medical conditions I could not make the payments and I was handed over to Colmed. There was in total R314 outstanding when I was handed over, I have paid R300 till date and been sending e-mails to Colmed to find out what is the situation. I received the following email this morning

"We received a remittance from Colmed Dated 01.08.2022 were they only going to pay R155.54 but we didn’t received any money from Colmed"

I feel that I am not going to make other payments except for the R20 and odd rand I am still outstanding. This was an agreement between Colmed and Valleyview Healthworx. I wont be paying any money double. And if they did not receive the funds from Colmed they need to sort it out with Colmed