[USA/PA] Medical company claimed they take insurance, then waited six months and dropped huge bill.

My friend (yes really) was seeing a therapist for six months. The company had his old insurance information on file, but he told them that he changed insurance and they told him (verbally, no proof) that they accepted his new insurance. They never got the new insurance information and let six months of appointments go by without ever properly submitting billing to anyone.

Then they suddenly got in touch with him and dropped a bill for the full six months, claiming they did not take his new insurance after all.

This company has something internally which they call a "No Surprises Act" just to put that out there:

https://lifestance.com/no-surprises-act/

Don't they have some kind of legal responsibility to keep him informed in a timely manner if they are unable to properly bill his insurance so that he has the chance to stop using their services and search for a provider who DOES?