Co payment on medication out of the blue?

Very frustrated with Discovery. Have always had only good things to say but all of a sudden im being charged a co-payment on medicine i get every single month (for more than a year now). The pharmacy advised me to contact Discovery and try and establish what the reason is. I was put on hold for over 20 minutes and eventually gave up. Is there no way this can be done digitally? How can i get this resolved??