Gmail App Password Not Working. Follow the instructions to enter the app password (the 16 character code in the yellow bar) on your device. They get a notification saying:
Open the settings app on your device → tap on mail. Sign out gmail account and sign back in. Gmail is working again on your iphone or ipad and you can send and receive email using the mail app.
By following this step you might end up erasing your gmail signature, drafts, ringtone, play store data, and other settings.
Try changing the passwords of your email account. When i sync, it states that my gmail account is not available. You can turn off access for these apps, which we recommend, or turn it on if you want to use them despite the risks. 7 tips to fix gmail not working problem 1.