How can I get rid of Google services pop up ads!?

I have a HTC one m8 (which is the best phone I've ever used, EVER!) and since the recent update (5.0.1) I've started getting pop up ads from Google services. It's a full screen ad and it's driving me insane. I've tried ad detectors, anti virus, force closing the app and none of it works. I'll put a screen shot of it up in the comments, please help!

You must have installed some 3rd party app that causes this add to popup, for sure its not from google o.o

Do you have AppLock free version installed? If yes, that app by default uses the full screen ad, you do have a choice to switch to banner ad instead though.

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