I have the exact same issue here on my 2018 iPad Pro 11" since last night!
Not the beta. I have never tried any beta. Just straight forward updated from iOS 14 to 15.
And on my iPhone's "Find My" the iPad is apparently "offline" not sending its location status to the server.
Unbelievable that this happened with a official release of iOS 15... I really need to fix it ASAP but have not found a solution yet.
Corlation
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