Adding the ugly version of the insurance point, because "contact them before treatment" is stated everywhere and the consequence is not.
I did not call first. I was ill, I went to a clinic, I paid, I claimed afterwards with every receipt. They took nine months and initially refused on the grounds that the facility was not approved, which I could not have known because I had not called the line that tells you.
It was eventually paid. The lesson is not that the policy is unfair, it is that the phone call is the thing the policy is actually about.