I installed a levitron 7599-ri GFCI to replace a standard 2 plug receptacle in my sailboat & the GFCI is not working. The Receptacle is the first outlet in-line and has 4 other standard receptacles after it.
When installed the green light on the GFCI illuminates but the outlet and the other downstream outlets no longer work , i.e.no power.
I did push the reset/ test buttons but they do nothing.
I switched back to the old non-GFCI outlet & it works fine again.
Have you confirmed that you do not have your line and load connections reversed? Disconnect the load terminals and then see if you have power at the GFCI by plugging in a device. If no power then you have your connections reversed.