I have a Galaxy S7 and have recently started receiving pop-up ads with sound that take over my screen even when the phone is on Do Not Disturb. It looks like they could be coming from Google Play as they have a triangle in the corner. I have gone to the Google Play App to block notifications but that doesn't seem to be working. I don't see any malicious apps that I can see in my apps. Does anyone have other suggestions other then a factor reset?