I tested 3 browsers, Firefox (what I use), Chrome, and Edge. I am using echo to show the value of the variable, and the value does not change at the same time I update the browser, I have to wait for 2 to 3 minutes and then refresh the browser again and then refresh. This procedure is every time I change my script, I'm only using 2 lines, one for variable and one for echo and nothing else.
Does anyone know how to solve this? I have already used .htaccess and apache conf changes and have not resolved.