Discovery Vitality ***** tactics

I participated in a Apple Watch program whereby you have to earn points through exercise monthly or else get a charge. This runs for a 24 month period. I was notified that for the last three months that I didn’t reach the target points and they needed to charge me. I then agreed with the agent to charge my Discovery credit card. Today without warning I received a letter from an attorney demanding immediate payment. Discovery didn’t use my preferred method of contact and even though they sent emails to a blocked account proceeded to record on the system that they contacted me three times before escalating. This is absurd, I decided to close my fully paid up credit card account with them as their dealings with me has been nothing short of disgusting and dishonest.