Why do I get pop-up ads every few minutes on my new phone ?

[22left]

On my new LG V30 phone, I get annoying pop-up ads which cover the entire screen, interrupting my work. I tried all settings including ad blockers, etc. I also tried downloading apps which promise to block ads but don't work. My 2 other LG phones do not have this problem so its not coming from the network. The ads even appear while the phone is off. Please help.

 

[Rukbat]

Some apps have random pop-up full-screen ads. Some websites are infected (the ads are actually viruses - the payload is the ad). You could also try Full screen ads. How to find the culprit.