Welcome to the Community @sucker
Could you provide more information? Normally the only things covered are those explicitly shown as being covered although some funds do ‘footnote’ certain exclusions.
As you unfortunately learned it is always advised to confirm cover or lack thereof prior to a procedure, rather than possibly getting an unexpected surprise afterwards.
Since this is specific to Bupa I am merging it into the Bupa topic, although another appropriate one may be
https://choice.community/t/bupa-and-hbf-cut-health-insurance-benefits/15205/11
as well as the network providers that need to be used.