Play Store not Working

[Loreta Scicluna]

I just bought the S4 two days ago. The Play Store was working fine. When I tried to log in yesterday, I was told Authentication is required. You need to sign in to your Google account. But when I tried to sign in, I got a pop up menu with the words, redeem,settings and help... I can't redeem, because I have nothing to redeem with!
I rebooted and also cleared cache, cookies and history, even though the phone I've only had the phone a couple of days...
Ant help would really be appreciated, thanks...

 

[Bosbouer]

Only time I see the redeem popup message is when I am already logged into my Gmail account and open playstore. By default, if you have an active gmail account on your device, the playstore should open.

 

[Loreta Scicluna]

But that's just the problem. I can't sign in to my account, just get the redeem pop up...