Where can I get good advice about Medicare supplemental insurance?

I’m thinking about changing my supplemental insurance. It’s very expensive, and I still end up out of pocket on ordinary charges such as routine visits to a podiatrist or dematologist.

The thing is, I know what I’ve got. I’m worried about making a change to something that looks good or better but isn’t. My late husband had cheaper coverage with another provider, but he spent a lot of time on the phone arguing for denied charges. I don’t want that.

I need some reliable advice and recommendations. Any ideas how to get them?