how to remove pop-up ads on my phone?

[AC Question]

every time I unlock my phone, a pop-up ad appears on my screen, and when I want to close it, it takes me to a website (www .zaka123. com / ....) then redirect me to another (m .letstravel. site/mobile), I have already done a factory reset and I have tried many antivirus, antimalware, airpush etc ... but nothing seems to work.
Sometimes a strange icon appears on my home screen, entitled "Travel".
No bizarre application in my application manager, and I think I have never installed an application from an untrusted source.
Help me please!

 

[B. Diddy]

Welcome to Android Central! Which phone? Do another factory reset, but this time after the Setup Wizard is done, go immediately to the Play Store and prevent any app from automatically installing. Now see if the problem persists. If it does, then I'd be concerned that you have malware that has installed itself to the system root. That can be hard to get rid of. You could try reinstalling the firmware, but the ease of doing that depends on which device you have.

 

[JRAshurst]

I have the same problem on my Doogee voyager dg300. No idea where the pop up is on the phone.

 

[JRAshurst]

Have you had any luck removing the pop up ad?

 

[Jovian Marwa]

I have the same problem no luck

 

[Kokoline]

Same problem, same mobile phone. I tried every antivirus but nothing. I've done factory reset, nothing... It's like that since I have this one, at least 6 months ago, and it's worse and worse ... I think the best thing to do is to buy a new phone ahah.