Worst healthcare insurer around

Oneplan are the worst people to deal with. They have sent me a letter of demand for R280 for services rendered after I cancelled my policy. I pointed out that I had sent a copy of the last invoice from the Dr via the Oneplan app but it would not go through. Eventually I have up as they did not respond to my request to settle the matter. Now months down the line I get handed over to their legal department. Once again I sent proof of the invoice concerned and all I get is that I still owe them R280. A different call center operator deals with each email I have sent so this goes unresolved. I am at wits end with these people. Very unprofessional company to deal with. One just has to look at all the negative comments about this crowed which far outweigh positive feedback.