Lincare Holdings – Billing scam

I didn't meet the 3-month compliance requirements for CPAP usage. Instead of giving me any options in writing, Lincare sent a bill for $450 to collections without notice or explanation. I received bills every single day so decided to just pay the fee to stop the harassment. After paying $450, I'm still getting bills saying they are proceeding to collections. I've been on the phone with "customer support" for 2 hours today and no one has any information as to what is going on—they basically stole $450 from me and are going to ruin my credit score anyway. Unfortunately that we have to get lawyers involved for what should be straightforward billing questions. Also worth noting that Lincare doesn't have any email addresses or ways to contact customer support via writing—that means there's no paper trail, and they can continue to scam people.