iCloud Find My saying "No Locations Available. All devices are online, but cannot be located."

See the articles If Find My is offline or not working - Apple Support

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

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.

Change your default browser from chrome to safari see the article Change the default web browser or email app on your iPhone, iPad, or iPod touch - Apple Support ( find my is compatible with google chrome 35 ) .

Find My - Official Apple Support