wondering whether a phone is really unlocked or not

[Binzer]

I got a phone from the lifeline service "Airtalk Wireless" which is a free government phone service in America.  I finished paying it off and don't use the service anymore. I was wanting to sell it as an unlocked device.  Their chat service tells me their phones are locked and they "can't guarantee" whether their phones can work on other networks.  But I used the imei checker on tracfone, verizon prepaid, t mobile prepaid and like 2 others and they all said it was compatible with their services.  so i'm confused. 

 

it's an s8+ that was originally from spectrum i think because their logo pops up when booted.  i guess airtalk buys devices from other companies.  it was advertised as used.

[SlayerOfHellWyrm]

If you carrier says it's locked, it's locked. The IMEI check only tells you if it could work on their network, not if it's unlocked. Call the carrier and ask them via a person, and then ask about getting in unlocked if it is. Should be able to get that done for free.

[Lordmage]

those free government phone are usually old CDMA/VMNO carrier locked regardless if it is paid off or not. but as above only a person with said carrier can confirm