I had a similar issue when doing some work. Removed the GFCI, marked the outlet to make it easier to rewire. When I put it together I reversed the hot lead side. The GFCI would not reset. Took some head scratching since that outlet was hot, but nothing else. Finally, used an outlet tester w/GFCI test button to figure it out.
Killed shore power, reversed the hot leads and BINGO!
Power in all sockets.
It's easy enough to reverse the leads on the same side. GFCI will not work if either side isn't correct.