Have you had to change your Google or Gmail password recently and now your phone doesn't sync?  Below is how to change the password in your iOS, iPhone or iPad.   I have attached a helpful video to show exactly how to change.  Hope it helps!

1.  Click Settings

2.  Scroll down to Accounts & Passwords

3.  Click on your Gmail account

4.  A box will appear for Re-enter Password, click box

5.  Fill in your password, if you use two-step authentication like a Google Text code, enter there.