Legal Question in Traffic Law in California

This is a confusing question. It is better for you to describe your actual case.

If you mean your own insurance company, you can get medical treatment only if you have medical payments coverage or, if in the case of getting hit by an uninsured or underinsured motorist, if you have uninsured motorist coverage.

A third party and "liable" insurance company will pay if you were not at fault and if you were injured.

Or, are you talking about failing to disclose a preexisting condition and your own insurance is refusing to cover you?

You should talk to an attorney.