MoveTo will only work if the location is valid. I had one instance when the z number meant the location was under the floor, so MoveTo wouldn’t work. (SimpleMoveTo would sort of work, but only because it didn’t try to understand that the location was unreachable until it got closer). The fact that your Wait task never gets fired makes me think that is the most likely solution, because the MoveTo never returns true, because your character never gets to the location.
On top of that, it sounds like your random number generator might be bugged. Can you post the screenshot of the blueprint? You need to try another random number if the current one is invalid, or maybe it is generating non-random numbers.
You could also check that the location is within the nav mesh volume, or try increasing the distance that the character has to approach the location to register as successfully getting there.