My live photos turns to short videos

Good afternoon Oktasis,

Welcome to the Apple Support Communities!

It sounds like you are having some issues with Live Photos and iCloud Photos and we'd like to help.

To help us understand the issue, can you provide a few more details?

• Where did you upload the 4,000 + photos from?

• Is this a Mac or a Windows computer?

• Are you viewing the photos on the computer or at www.iCloud.com?

• What application are you using on your computer? Photos for Mac? iCloud for Windows? Microsoft Photos?

• Did you have iCloud Photos enabled on your iPhone 12 Pro Max?

Set up iCloud Photos on all your devices - iCloud User Guide

Live Photos are only 3 seconds in length to begin with, so we are not quite clear what has changed.

Take a look at the resource below to understand how they work:

Take and edit Live Photos

We look forward to your response to the questions above. This information will help us determine the next steps to resolve the issue with you.

Take care.