Question about Physical Therapy unexpected bill

I live in Washington State.

I had a physical therapy visit based on my dr’s recomendation. Prior to my visit I had to do insurance paperwork and was told that my insurance (Aetna) requires a $50 copay, which I was aware and agreed to. I only had one visit with them as I didn’t think I would see any benefit in continuing my visists with them and stopped going.

Almost 2 months later I receive an email with a bill saying I have to pay $190 more. I reached out to them and they said to discuss this with my insurance. My insurance said I was billed correctly as that amount was applied towards my deductible which hasn’t been met yet.

Called the PT place back and the billing agent said they check insurance prior to the visit just as a courtesy and that the final billed amount is not guaranteed. She said they can’t do anything about it anymore as they would be commiting tax fraud.

My frustration with this is that at no point was I made aware of how much money I would be expected to pay. Had there been an advance notice like: Consultation fee costs $250, you may have to pay the full amount, I might’ve reconsidered going there. As far as I was concerned during my visit was that my insurance approved it and I just have to pay the copay.

When I told this to the billing agent, she said they’re not required to disclose the amount and that the rate can vary by time of day and date of visit so they can’t communicate that in advance. It is only up to me to talk to my insurance before my visit to find out and to know my benefits.

I’m pretty much ready to pay the bill at this point but just wanted to see if there was something I’m missing and otherwise what I could do better in the future to avoid surprises like this? Should I be calling my insurance before visiting a new doctor/place and double check with them?