What to do with my iPhone 4S?

I got an iPhone 4s from Virgin Mobile USA (at a Target) in the beginning of November 2012.
Over 2 weeks ago, my 3G could not connect to the internet. It keeps saying "Could not activate cellular data network." Occasionally, beneath that message it also says, "Your are not subscribed to a cellular data plan," which I'm because I have the beyond talk plan and I already paid for this month.

I've tried everything to fix it! Toggling airplane mode, data, location, turning the phone on and off, resetting the network settings, dialing ##UPDATE# (at first it would say service update failed and now it doesn't even say that), resetting the phone, and erasing all content and setting (3 times!), updating both the software (to ios6) and the carrier settings through iTunes and I still get the same message! I tried to even change the APN settings (but I never found Virgin's APN for the US) so I used Sprint's and nothing too.

I've been talking to Virgin reps over the course of 2 weeks and they still haven't helped! At first they said it was an outage and told me to wait. So I waited, then they told me that they were having an internal system and told me to wait 24-72 hours twice, and I did. Then someone told me my account was in the updated system but didn't know why my 3G still wasn't connecting. They've refreshed and reset my settings and profile on their end and still nothing. I've been on the phone for over 2 hours being asked to do the things I've already done 2983098439042 times and all they do is transfer me between reps, techs, and iCare techs. Not to mention, they even tried convincing me there was an outage a day ago even though my husband's Virgin Mobile iphone 4s worked flawlessly! As well as my brother's android on Virgin.

I eventually took my phone to an Apple store yesterday and the guy said that the only weird thing is that my phone is not unlocked (it says "false" so it must be locked?) which is obvious because Virgin locks their phones onto their network. My husband's iphone 4s says the same and his is fine. They said there was nothing else wrong with and that they could give me a replacement unlocked Sprint (even though it's not really unlocked like a GSM carrier) but they can't guarantee me that it will even activate on Virgin's network and they're afriad I'll be left with a brick. They also said my phone has no microsim and that sprint's and verizon's iphones have them even though they're a cmda network. Too bad Virgin doesn't even have the sim card.

I don't know what to do now! I can't return the phone to Target since it's past 30 days and i lost the receipt. I don't even know if anyone would buy this phone like this (as I can't spend another $500 on a new phone).

Anyone having the same issue? Anyone got it fixed? Can someone help? I know this is long but I'm so frustrated. I have to pay my next bill next week and I don't want to if it's going to continue to be like this. That'll close my account but I'll still have no phone. Please don't suggest to go on a contract. I know their phones are cheaper on contract but their plans are generally more expensive and I don't want to be tied down for 2 years.

I can only call and text (no imessage).

Give it to me

I don't think it has anything to do with the phone, I think its your carrier. I would tell them you can't pay them if they don't have service.