Traceman

We recently rotated our hot tub and built a deck around it. Doing so we had to install a junction box to lengthen the wired to the outside disconnect. We filled the tub up and flipped on the GFCI breaker but it does nothing. No info or lights on the screen or anything. I took a meter and incoming voltage from neutral to each load wire is 120 and neutral to ground is 0. I ohmed all the fuses and they check good. What can I be missing?