F8 key opening single player server whilst using another server

[Grimberian]

Whilst player in another server the F8 should open the skills menu! but a few days ago i opened up a single player using a map so i could build because he server had tools which am accustomed too. but since then the f8 key close my link to the server i am playing and then opens the one i used so i could build! how can i re command the key or delete the single player mode so it doesn't effect the f8 command on a host server i play? Thanks in advance !

[Rubat]

I have no idea what you are saying, but type "unbind f8" into your console.