Cannot tick "allow executing as a program" - it unticks itself

I am not sure how many files that this happens to, but it has happened to two that I have tried in the last few days, one .sh file and another program/executable. I am logged in as root - Linux Mint 21.2 When I try to allow executing as a program it unticks itself (as in this video) I also get 'permission denied' in terminal, as root and i have tried

chmod +x filename

and

        sudo chmod -v +x filename.sh

    sudo chown --verbose 1000 filename.sh



  

But still get denied.. What am I doing wrong here or how can I fix this?