You are getting ads in phone app also? That is not possible. You are having some issues with some other app which ia showing ads in your apps. Weather app shows ads I know, but it doesn't show like crazy.
Go to phone app, then settings, then other call settings and turn off customization service. And if you have an extra option of "Places", turn that off. Although all these could be done while setting up your phone.
Already Did, I think i have to reset my ad ID as well, but the point is why as a customer I have to turn it off, It's a flagship device it shouldn't be like this, Samsung competes with iPhone there shouldn't be any ads on stock apps period.