(from the post) Tableau is checking to see if the host has changed. This can happen all the time in the cloud, for example GCP has a live migration feature that keeps you going even if the underlying hardware fails. Also, restarting a VM is not guaranteed to boot up on the same host.
The problem: Support cannot reset the license count, until you have reached the limit (max of 3 activations), i.e. participated in a lottery and hit the jackpot by locking up your system:
https://kb.tableau.com/articles/issue/error-tableau-server-i...