I bought an iphone from letgo, and it has a message Iphone disabled, connect to itunes What can i do? I can't find the seller either?

I bought an iphone from letgo, and it has a message Iphone disabled, connect to itunes What can i do? I can't find the seller either?

Added (1). Some more clarity: Letgo is an app where you meet a person and buy the item. He showed the iphone and it was out of battery, I took his work but once i charged it up, there was that message. I contacted letgo but they can't seem to help me. He has deleted the app itself

IPhone screen black with lines?

My phone screen is cracked and I assume water vapour got into it since it was in the bathroom during a shower. The screen turned black with lines after that when I tried to use it so I immediately turned it off and put it in rice. Is the phone completely broken and its a waste of time to put it in rice? How long should I leave it in rice if it should stay in there? It is not easy for me to get a new one so I'm really hoping to fix it.

What happens if customs seize a package (Australia)?

I'm thinking of importing a gun-shaped phone case for my iPhone X for a YouTube project, but I'm not sure if this item would fall as a prohibited item in Australia and what customs are likely to do if they seize this item. My goal was to wirelessly pair my iPhone to my car's audio system and then pretend to shoot people with my phone in this case while running a gun app that makes realistic sounds that plays through my car. Speakers. It's a prank video fro my YouTube account.

The phone case looks like this one.
https://www.macrumors.com/2016/07/07/man-charges-carrying-iphone-gun-case-airport/

Are gun-shaped phone cases illegal?

I'm unable to find Australian laws relevant to the importation of prohibited items to Australia.

Added (1). I've just done some research and found out an imitation firearm or a product that resemles a firearm is considered a deactivated firearm according to Customs (Prohibited Imports) Regulations 1956

Customs (Prohibited Imports) Regulations 1956
https://www.legislation.gov.au/Details/F2016C00795

How come songs suddenly start playing in my head sometimes?

Like just now, Michael Jackson's "Thriller" just started playing, COMPLETELY out of the blue, I wasn't thinking of it, or listening to it (or any other music) it literally just came from nowhere.

It's as if my brain is LITERALLY an MP3 or iPod device that just started playing music by itself (like my iPhone does every once in awhile).

This is more common in my brain than on my actual phone, what is this?

Could I actually have a chip implanted in my head like that guy on Dr. Phil?

It is LITERALLY like my brain has an MP3 built in or something, it's kind of unnerving how clear and realistic (as if it IS an iPod or MP3) it is.

Is this even normal?

Why does my iPhone do this? - 3

My phone will be at full brightness and suddenly it adjusts down a level without transition, so the dim is very obvious. I open the settings and it claims the phone is still at full brightness even though i saw it dim. And no, my auto-adjust feature is turned off. Why is my phone doing this?