Welcome to the Community!
Nobody likes a pop-up ad.
Could you please give us more details about this?
Where exactly are you seeing those? Do you have any examples?
Let us know!
Hmm, If they come up the moment you open the screen, on your main screen at that, it definitely sounds like an app is pushing ads to you.
Can you try to uninstall the last few apps you have installed to see if that solves the issue?
Keep us posted!