Lost ipad

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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 have been lost.

Any data locally stored on your iPad is secure. Until or unless your iPad has a network connection - over which it can transmit its location and receive remote management or erasure commands - attempting to remotely erase the device will not be successful.

Until you are absolutely certain that your iPad is unrecoverable, you should not delete the iPad from your list of devices.