How can I check if my iPhone 16 Pro Max is blacklisted or not?

I think you were told what the problem is. You bought a stolen iPhone which is blacklisted and can't be used. Return the phone for refund. It's useless to you.

This user tip also speaks to Blacklisted or Stolen phones --> https://discussions.apple.com/docs/DOC-250001038

Most likely, you bought a stolen iPhone. Where did you buy it, exactly? From an Apple Store or an Apple Authorized Reseller? If it wasn’t either of these then you bought it from a fence (a stolen property reseller).

You can check yourself to see if it was blacklisted in the USA→CTIA Stolen Phone Checker

The problem is you bought a stolen phone. It's a brick. It can't be activated. You got ripped off.

If you can't return it and get your money back, toss it in the recycle bin and take this as a life lesson.

According to you, a carrier told you that this iPhone 16 Pro Max is blacklisted because it was reported as stolen property.

I don't know about the laws in Afghanistan, but in most jurisdictions in the U.S., there is a crime called "receiving stolen property." For instance, a Google search found this on what seems to be a Pennsylvania government site.

§ 3925. Receiving stolen property.

(a) Offense defined.--A person is guilty of theft if he intentionally receives, retains, or disposes of movable property of another knowing that it has been stolen, or believing that it has probably been stolen, unless the property is received, retained, or disposed with intent to restore it to the owner.

(b) Definition.--As used in this section the word "receiving" means acquiring possession, control or title, or lending on the security of the property.

If this is a second-hand phone, and there is good reason to believe that it is stolen property, you may want to turn the phone over to the police, together with an explanation of how you learned of the phone's status (from the U.S. carrier), so that you do not become guilty of this crime. 

wahidahmad82 wrote:

Thanks a lot

but I bought this new full pack with sealed box from the shope

i have the bill with me

Then you need to contact the "shop" you purchased the phone from. They really shouldn't be selling stolen phones, boxed or not. Is this "shop" an authorized Apple Seller? If they are, you should be able to find them here --> Find Locations

The machine to seal boxes and make them appear to be from the factory costs under $100. So the fact that the box was sealed proves nothing. That’s why Apple and other manufacturers have added tamper-resistant self-destructing “tabs” that must be removed before opening the box.

One thing to check is whether the iPhone was really new. Enter the serial number into this site to check→Apple - Support - Check Your Service and Support Coverage

wahidahmad82 wrote:

The phone had the seal and the seller open the seal in front of me.

So what? If it was actually still factory sealed, all that means is that it was stolen before the box was opened.

You can argue about it all you like, that's not going to alter reality.

You purchased a stolen phone. It has been blacklisted. It is not usable. Nothing you can say or do will change that.

Return it and get your money back or turn it over to the police.

Someone reported the phone to be stolen.

Let’s say for a moment that this “shop” sold you a brand new, never before sold at retail, phone. (Note carefully that I am NOT agreeing that they did; just considering the possibility)

How, then, do they explain the phone being blacklisted? Wouldn’t that suggest that you have a rather major issue with this “shop” and that it is them - not us, not Apple - who have a LOT of explaining (and making things right) to do?

Take them back to the "shop" where you bought them. If they refuse to give you a refund, take them to the police and tell them where you got them. I imagine a fair percentage of their inventory is made up of stolen goods.

wahidahmad82 wrote:

i checked and it shows under warranty up to end of 2025

That is not relevant. Warranty doesn't have anything to do with whether it's stolen or not. Apple does not track stolen devices.

The warranty should be exactly one year from the date you bought it; for example, if you bought it on December 31, 2024 the warranty end date should be December 30, 2025. So if the warranty end date is less than a year from the date you bought it then you bought a previously owned iPhone.