My tvs resalution what fix

[CylicSnailfood]

The other day i was on my computer and i wonted to see what would happen if it would change to 1920x1080p my friend told to try it to see if i like it it made my screen look funny so i went to change it back my computer changed it to 1366x768 but my tv is stuck at 1920x1080 and it wont change back this is only on my desktop when i got to games and run them the tv will change to 1366x768 iv bine thru all the settings in my tv and computer but yet i don't know how to fix it
Note: this is a Samsung tv

 

[hang-the-9]

Your post is a bit confusing. What is the native resolution on the TV and the monitor you are using? What the resolution should be depends on that, and also if you are using duplicate or extend settings on the system.