Try going into settings/apps and clear GMail cache and data, delete the app, reboot your phone, redownload the app. If that doesn't work, try clearing cache and dalvik cache in recovery. Good Luck!
I am sorry to learn your phone is constantly restarting itself. I know how frustrating that can be. I would like to thank SoccerRef12 for providing great troubleshooting steps. Have you tried these steps? Is your phone still resetting itself?
If your phone is still resetting, can you try removing then readding the email account. If your phone is still resetting, please feel free to reach out to us for further assistance. Have a great day!
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