If you are entering the Gmail password and it keeps through you back to the Gmail login page. there could be several reasons behind it.
1. First of all, you need to clear the browser cookies and cache data.
2. you are getting incorrect username or password error message along with the login screen. this means, you are not typing the user credentials correctly. so you need to reset the gmail account, and then retry to access your Gmail account.
3. Please Check your email for any security alerts from Google.
4. Make sure you are entering the correct code from your authentication app or phone number. this is applicable if you have enabled two step verification on your device.
5. Check your internet connection and make sure itβs stable.
6. Disable any unnecessary browser extensions or plugins and try again
Once you will make these changes into the Gmail account, your device will start working fine.