If you are using Google Chrome and dealing with the issue of then check the device you are using is connect to the internet. Proceed to Chrome settings and remove cache files and cookies by following the steps properly. Launch Chrome and choose three horizontal dots and choose settings from drop-down menu. From left-hand panel, click to privacy and security options and then clear the browsing data. Choose a time range at the top and checkmark all three options appearing on the screen and then click to clear data. Lastly, relaunch the Chrome on device and check whether the Gmail not working is resolved or not.