I bought a used iPhone with a SIM card?

So I bought this "like new" iPhone 5s of eBay and when I got it, it still had the SIM card in it and it's from T Mobile, is there any way I can activate it again? If not how can I get a SIM card for my used phone without leaving my house and activate it.

SIM cards from T-Mobile are cheap. Just buy a new one and don't risk anything.

You can trim your current SIM card to nano-SIM and use it with the phone. If your SIM is not from T-Mobile, you need to unlock the phone to use it on different carrier as the phone is locked to T-Mobile only. If you need help with getting the phone factory unlocked, mail me for references.

Just call t-mobile to activate the sim you have, then hope the phone was not reported as lost-or-stolen.

When buying phones on ebay, always make sure its a reputable seller and not someone new, I hope you did that…