GFCI Not Working, No Power
In feed-through wiring, only the first GFCI device in a chain displays a trip indicator — every outlet downstream can go completely dark with no obvious sign of what tripped.
A simple order of operations
Check the breaker panel first. A tripped breaker will make everything downstream look dead, GFCI included. Reset it and see if power returns before touching the outlet itself.
Next, look for another GFCI outlet earlier in the same room or circuit — it may be the actual device that tripped, even though the dead outlet you're looking at is somewhere further down the chain.
If both of those check out and the device still won't reset, treat it as a likely internal failure or wiring fault rather than continuing to press the same button.