IPhone XS Max notification issue, how to fix?

New iPhone XS Max shows notifications on lock screen even if I had the phone unlocked and open when they came through.

So for example, if I'm using my phone and a notification appears that I don't view, it will later appear on my lock screen when I turn the phone off.

What do I do to fix this, as I get confused thinking I have a new notification, when really I don't?

How do i handle this? (Ebay)?

I ordered an Iphone from ebay but when the package got here it was empty just the box no phone, i told the seller and he told me to open a case that he already talked to customer service but when i opened the case ebay closed the case and denied me any refund because "The package was delivered" yea but there was nothing in it $220 down the drain or what can i do?

How to stop screen time on iPhone?

My parents (smh) set a limit on my screen time through the screen time setting on iPhone. They made a password so I can't turn it off. Any way I can stop it from tracking? Like clear the app or something?