gamma glitch

I've tried to change my gamma multiple times but every time I restart. the gamma changed back to 1.0 even if I put it to 7.0 or 10.0 or even 100.0, it keeps changing back to 1.0 is this some new program at work or a glitch? and yes after making the changes each and every time I saved the changes. so why does it keep changing back to 1.0?

I've tried to save & quit, start again changed back. save & quit then closed the page reopened minecraft and again it had changed back. even after opening resource packs changing my gamma saving the changes and closing option menu and reopening it. it changed back again.