I signed up with them and the plan was R2500 which already I will struggle to afford

I signed up with them and the plan was R2500 which already I will struggle to afford. But without even notifying me they have increased it by R500 late joiner penalty. But are they not supposed to first discuss it with me before automatically making me a member? They requested proof of previous medical aids which I provided. Except for one that has apparently closed down so I can’t get my membership certificate. I send them the documents and then a day later they say I need to provide proof of previous memberships. I would like someone to actually call me. My debit order is due on the 25th and I want it sorted before then.