Discovery messing with my medical cover all in the name of Vitality

I left Kaelo Health thinking I'd get a better deal with Discovery Flexicare but that didn't happen. I initially joined Vitality too but soon decided it wasn't worth it BUT I kept up with my monthly premium for Flexicare. Last week I visited the doctor for the first time, and mark my words, there was a problem. I found out that I was in "arrears" because of my missed premiums for Vitality? How can Discovery allow my medical cover to be affected by something stupid and frivolous like Vitality? And why wasn't Vitality cancelled after my first missed premium? So now I have to pay the doctor out of pocket while Discovery ignores my emails. I am not impressed and will have to find another medical insurance.