Skill unassigns itself when changing zones

Hello,
When I change zones (from my hideout to a map, or from a map to an abyss, etc.), my Twister skill — which is assigned to right-click — automatically unassigns itself, and I have to reassign it manually every time I change zones.

I’ve tested it on other key bindings as well, and the problem is the same.

What can I do to fix this?

EDIT :

The skill stay when the level of gem is 19 but it unassigns for 20 or 21 ...