[Client Bug] ` (Left Quote/Tilde Key) Can't Be Assigned as a Hotkey

I've been having a weird bug recently. When I try to assign ` to a hotkey ingame, it functions for the rest of my playtime that session (even across multiple games) but reset once I close the client. And when I do it in the client, it ignores it completely and immediately resets it. Perhaps it's an invalid character or something? I'd love to use that key for wards so I'd really appreciate it if anyone has a solution. Thanks!