Switching from StraightTalk to AT&T

Presuming you want to keep your number, you need to port it. Take your new SIM card to an ATT store to port your number. If you bought that iPhone from Straight Talk, you might also need to get it unlocked. Contact Straight Talk for that.

Yeah. I bought the phone from Walmart and that same day I also bought the StraightTalk card and activated like last month which is expired

I believe Straight Talk requires 12 months of services before they will unlock.

Dang, so I would have to stick with StraightTalk?

If you want to keep using that phone, yes. You could always sell it and buy a different phone.

Alight, I gotchu! One more question, sorry for these, would it be possible to by another sim card and insert it in the phone?

Another SIM card from where? Another Straight Talk sim? If so, sure but you probably don’t need a new SIM card. If your Straight Talk service just expired, you should be able to restart service.

If I'm right the sim card is the mini chip that came with the phone package. Is there a way I could buy another one of those?

Yes but again, you probably don’t need one. A new SIM card means a new number. You can probably keep using the SIM card you already have, just restart your plan.

Oh ok, I see. Do I like cancel my plan StraightTalk, but it's already expired like restart the plan but have it as AT&T since I want it as AT&T