Hi there Terimbax,
I would be happy to assist you today. When a phone is gone through a factory reset, there isn't much you can do. Here are some options that may be useful.
Tracking apps:-
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If you had the foresight to install some tracking type apps and move it to the system partition via root, those can survive a factory reset (though the preferences may be reset).
Report it as stolen:-
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If you know the IMEI, you can at least report it as stolen. The cell companies can block that phone from their network (both CDMA (non-sim) and GSM (sim) networks can do this; CDMA networks call it ESN instead of IMEI). However, I highly doubt they will help you locate it, even if they could track it.
You can find the...