Sometimes apps doesn’t work properly because of the overloaded cache. When excess cache gathered in the apps then they need to be clear otherwise they may create many problems in running the app. Same as in Facebook you have to clear cache often. How to clear cache on Facebook on android device? To clear cache on Facebook, you have to first open the settings in your device, then click on the “Apps & notifications”. There search for Facebook app and click on it. Click on storage and cache, at last click on the “Clear cache”.