Can I sell a phone that I accidentally reported missing or stolen?

About a month ago, I was under the assumption that I had lost my entire purse. This included my debt card, iPhone 6s Plus, etc. I ordered a new phone that arrived to me within 2 days. However, a day into activating and using this new iPhone 6s Plus (a total cost of 200$), the purse I had believed stolen was returned to me with my old iPhone Included. I believed it was too late to return the iPhone 6s Plus I payed 200$ for to my insurance considering I had already activated it. Is it possible for me to sell my old iPhone 6s Plus even though it is reported lost or stolen? Is their anyway I can get that undone so it is able to be sold? Or is it fine to be sold as is under the sprint network?

The IMEI number of your old phone will have been reported as stolen, and if used it may be tracked or just fail to function at all. Also not when you were paid the compensation for it, the old phone became the property of the insurance comapny - and so it is no longer your property to sell. If you do sell it you could be charged with BOTH FRAUD and THEFT!

The insurance phone will need to be returned if you want to activate the old phone, that is if you actually want to sell it and NOT be a scammer.

The insurance company blacklisted the phone, because you reported it lost or stolen ON PURPOSE, not by accident. So the old phone belongs to the insurance company, not you, so it's out of your hands, unless you tell them you found it and want to reactivate it, in turn they will want the replacement back.

Once your phone has been reported lost or stolen, it almost becomes inoperable on any carrier network until the network barring is removed from the phone's unique IMEI number.