Not sure how to unlock the phone I bought

[microcosm]

Hi guys. I am really hoping someone can help.

I bought a second hand phone from ebay, as I have done before.  The advert stated the phone was unlocked so I didn't think much of it.

However, I put in my Smarty SIM and it is asking for a Pin code. I did some research and learned that this happens when a phone is locked to a specific network.

I messaged the seller asking them if they knew anything about this, and they said that they aren't sure what it could be since they bought the phone from Tesco Mobile and was told it was unlocked and they themselves used their GiffGaff Sim with it from day 1.

I don't really know where to go from here. I used the Tesco unlock request but not sure I did it right, since I used my Smarty number - the Tesco Sim in the box, that the previous owner never touched, does not have any service. I'm really confused and frustrated. I'd rather just sort it out myself and get the phone going since my old phone is very broken and I just need one ASAP. I think my window to file a PayPal dispute is closing, and I have never had to do it so I am not sure how they go.

Would greatly appreciate any advice on what I should be doing! Thank you.

[Chalkychap]

Sounds like handset is locked to the O2 network @microcosm.

Both Giffgaff and Tesco Mobile use the O2 mobile network for their services. Unlocking the phone is easier if you are the original owner. There are online tools for checking if the phone is locked, by using the device's IMEI number. A Google search should turn-up some options.

I'd ask the seller for a refund, as it seems the listing was incorrect/misleading.
Otherwise, get a Giffgaff or Tesco Mobile PAYG SIM, and see if either works in the handset, or start a dispute via eBay/PayPal.

Good luck @microcosm.

[Chalkychap]

If you bought a second-hand iPhone @microcosm, you can easily find out if it's unlocked or not.

Find out if your iPhone is locked by going to Settings > General > About.
If "No SIM restrictions" appears next to Network Provider Lock, your iPhone is unlocked.

[microcosm]

Hi! I contacted Tesco directly and they sent me the code I needed. So everything is working now! I didn't even need to prove I bought the phone originally or anything, just the serial number, IMEI (found on android under settings - > about > status) and my current details - didn't have to activate on Tesco by topping up or anything like that. Thank you! It was a lot easier to resolve than I thought, seemed too complicated and with a lot of caveats lol

[MSF]

Sorry if this sounds too obvious, but did you try the default 0000 for a sim? It may be that the phone has been set to require sim code at startup.