Gmail say “no connection”:

• 'There is no connect'-If you're having trouble with your iPhone or iPad, try the following: Check to see if you're connected to the internet. Close and then reopen the app. Sign out and then back in again.
• 'Permanent blunder'-When you try to sign in to Gmail and get a 'Temporary Error (502)' notification, your mail is momentarily inaccessible. This problem normally goes away after a few minutes, so try logging in again. Your messages and personal information are still protected even if you can't sign in right now.

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