Unable to turn off water supply to toilet

[greatdeals_007]

I tried turning the valve all the way off but the fill valve does not shut off. thoughts?

 

[Reach4]

Time to replace the stop valve. The quarter-turn ball valves are more reliable than the classic multi-turn valves.

Consider posting a photo of your bad stop valve at the wall.

 

[Sponsor]

 

[Terry]

Many older shutoffs may lose their seal over time. Options are to open it up and replace that seal, or to install a new one. I carry new shutoffs with me, so my preference is to install a new one.
You might have 1/2" threaded from the wall if it's from the 60's or older.
1/2" copper which can be a compression installation or may be soldered on.
About the 90's we started seeing CPVC which is a brittle plastic pipe.
More recently we are seeing more PEX which can be installed several different ways, including crimped, expanded and sharkbite.