Samsung does it again!
No person likes to be bombarded with ads, which is why most people end up deleting the apps that force ads upon them. It can be expected though that app developers will force ads since that is one of the ways they make money, but it is almost unforgivable for a major brand to advertise through smartphone notifications.
This is exactly what happened to a Reddit user "AlanRosenthal" who reported that he received pop-up notification to straight up buy the new Note9. This was not a promotional ad, nor a "special offer", just the regular "preorder yours today". If you don't want this to happen to you, you can disable ads by going to Settings → General → Marketing Information.
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