Simple tool upgrade kit not working

I’ve tried everything. I made 5 of them. the first 3 worked fine, and then the last two are bugged. I even made another, still bugged. Ive tried relogging. This is on a nonofficial server, no mods.

Update: I cant apply ANY more upgrade or modification kits to anything anymore.

okay wierd. the problem was a graphical error. It showed the item was full hp but then i repaired it, and now it works.