iPhone 15 pro max showing 1985 purchase date

Click on this link to read how to update your proof of purchase --> Update your proof of purchase - Apple Support

To update your information contact Apple Support by phone. Tell the advisor that you need help with your Apple Limited Warranty or AppleCare plan expiration date.

Here’s what you need when you call:

- The device serial number

- Your sales receipt

- Your AppleCare agreement number