I cannot turn off cache
Browsers can be pretty aggressive about caching. Provided you're not using some other caching layers like redis/memcache, varnish, or a CDN, I'd start by disabling the browser cache.

In Firefox, open the inspector and click on the gear icon in the top right to open the Toolbox Options menu. Under the Advanced settings section, check the 'Disable HTTP Cache (when toolbox is open)'. I think Chrome is very similar in this.

Also be sure to use the hard refresh option. For Firefox it's Ctrl+f5. https://support.mozilla.org/en-US/kb/keyboard-shortcuts-perform-firefox-tasks-quickly