See Last Location in Find My

Use the Find My app to locate a missing device or item - Apple Support explains under "Don't see your device?"

• ...
• If you're using the Find My app, you can't see your device's location if more than 7 days have passed since its last location was sent to Apple.
• If you're using iCloud.com/find, you can't see your device's location if it's powered off, the battery has run out, or more than 24 hours has passed since its last location was sent to Apple.
• Learn how you can still protect your information.

If a device is offline for over 24 hours, its last location is not displayed.

Contained in the Apple Support Article below is the following:

Don't see your device?

• You might not have Find My turned on.
• If you're using the Find My app, you can't see your device's location if more than 7 days have passed since its last location was sent to Apple.
• If you're using iCloud.com/find, you can't see your device's location if it's powered off, the battery has run out, or more than 24 hours has passed since its last location was sent to Apple.

See this --> Use the Find My app to locate a missing device or item - Apple Support

I don't know why it falls off the last location list after 24 hours. And we are all users on this user to user only forum. We don't for or have anything to do with Apple Services.

Feel free to provide feedback to Apple via this link about this --> Feedback - MacBook Pro - Apple