I am having a strange issue on my Nexus 5 for the last 5 days. My phone has stopped syncing to my google account. Now I am not getting mew mails on gmail app, I can't connect to play store, can't sign in to youtube ,can't see my google cards, hangout and google calender not working. I removed my google account from settings and tried adding it back but was unable to do so. I got the following error message"Couldn't sign in - Can't establish a reliable connection to the server.This could be a temporary problem or your device may not be provisioned for data services. If it continues, call customer care". Today I also did a factory reset on my phone and erased all contents but I was still unable to sign in. I even tried changing my google account password on my computer but still cant log in on my phone.
Here I would also like to mention that internet on my phone is working fine. And stock email app is able to access my gmail account. Kindly advise what can I do to get my phone to sync again.