[anti-abuse-wg] Receiving police order on not in use IP

Hi

We recently receive a Dutch police order requesting us providing customer info on an ip in which was not in use for past 6 month, we do not have record for the usage of the ip 6 month ago( so we don't know who used it 6 month ago as we simply don't record it). Police claim it has to do with crime without giving any details.

How should we react on this? Any suggestions? 

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