I had to rebind them in the menu to make them work. When I went into the menu, the ability was bound on 2 already but I rebound it and it worked. The same was true for the Enter key to chat.
I had a similar issue while Playing Goo Man. BUT my issue seemed to be around using the rails, my 2 would work while in base but after grabbing a rail it would break. Resetting my key binds did also not resolve the issue but leaving game and rejoining resolved the issue. After a certain point of the game something fixed it and I never had the issue again.
For me, this just happened while I was using Mo and Krill, except 4 wouldn't work. Both Chat and All-Chat were also broken-- it wouldn't even let me rebind the keys to them. I could still chat through console F7 > say_chat
