Lost or stolen iPad Pro

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Locate a device in Find My on iPad - Apple Support

Here is Apple’s advice for lost or stolen devices:

If your iPhone, iPad or iPod touch is lost or stolen – Apple Support

Use the Find My app to locate a lost or stolen device – Apple Support

If the Find My iPad feature was enabled prior to it being “misplaced”, then if active, you would stand a good chance of locating it. 

However, if the feature was not activated prior to being misplaced - or the iPad has been inactive for more than 24 hours, the last known location will not be available - and the opportunity to use technical means to recover the iPad may have been lost.

Without an active network connection, the iPad has no means by which to derive or communicate its location. If Find My Network is enabled within Find My iPad settings, the iPad may be detected by other devices that similarly participate - and an appropriate location might be reported via Apple’s servers.