TEST and RESET each GFCI receptacle.

Switch the GFCI circuit breaker to the OFF position and then back ON.

Sometimes they can look like they are On when not.

Yep. Sometimes that "fail open."

Take the cover off and use a VOM or a neon test to see whether you have
power coming to the GFCI. If you do, REPLACE it. If you don't look "up
stream."

Jim