Unusual activity in my iPhone. s3.eu-west-1.amazonaws.com

Checking my screen time I noticed that in the last few days my screen activity has increased from 3-4 hours per day to an average of 10 hours - even while at work. I then saw that I had 7 or 9 hours of an app or website called s3.eu-west-1.amazonaws.com. When I introduce the address in Safari to check, thinking it might be related to Amazon, a game opened up. Then I blocked this address on my iPhone, that was yesterday, but to my surprise I had again 10 hours of screen time - basically the hours the phone is switched on, which is impossible. I am afraid this might be some kind of virus. I made a copy of the data and erased my phone completely hoping whatever is in my phone disappears, and download the last back up. I am not very happy because I do not visit many sites and I always thought the iPhone to be strongly secure. Can someone tell me what can this be? and if by erasing the data it should have been removed? I am very concern about my personal data. Thanks