How To Fix Gmail Having Trouble With Google Play Service?

Go to 'Settings>Apps'. Scroll down and the 'Google Play Services' app. Tap it to open.

1. My Gmail account is showing "Gmail is having trouble with Google play services" how do I fix it?
2. How can the trouble that Gmail is having with Google Play services be fixed?
3. I have purchased a refurbished (second hand/used) Nexus 6.

How do I fix unknown Services With Google Play Services?

Make sure the All apps filter is on, scroll down and tap on Google Play Services. Tap on Uninstall updates and restart your device. Go back to Settings > Security > Device administrators and activate Android Device Manager. Wait for it to update again and see if the issue repeats.

How do I fix Google Play Services Has Stopped?

Unfortunately Google Play Service Has Stopped? Here's How to Fix It

1. Restart Your Device.
2. Update the Play Store and Google Services. 
3. Change From Cellular Data to Wi-Fi (or Vice-Versa) 
4. Change the Time and Date.
5. Clear Google Play Services Data (and Cache) 
6. Revert to an Older Version of Google Play Store.
7. Remove Your Google Account. 
8. Install a Third-Party Copy of the Play Store.