Data Problems (as in none): Nexus 4 with Straight Talk

Similar issue with me:

I have an auto refill unlimited plan with Straight Talk using their T-mobile equivalent sim card on a Nexus 4.
My problems with Straight Talk started a month after I started using their service. I would experience loss of data capabilities several days before my plan renewal date. After talking with Straight Talk Customer service the last time this happened, I requested compensation for the cumulative 15 days I didn?t have data service. Their representative told me they would extend my renewal date by 5 days. As I had just paid the day before which was June 10th, I wasn?t expecting to pay till July 15th.
My expectations of smooth sailing with Straight Talk were thoroughly dashed to the rocks. The very next day, after I was assured my compensation and that I would not have any more data problems, my data service was once again unavailable. After talking again with Straight Talk customer service they told me they weren?t sure what was wrong and would put a ticket request in with their engineer level technical support to review my problem.
Furthermore, on the 15th of June my phone was deactivated by Straight Talk. When I tried calling customer support on another phone they told me I had to pay for this new month even though I had just paid 5 days earlier.
Eventually my phone was reactivated, but still no data.
I?ve had 5 tickets put in and ?re-escalated? to top priority, with each time taking a turn around period of 72hrs, and even had a replacement sim activated to no avail.
Curiously enough, my fianc? has a nexus 4 with a straight talk sim, and when I place it in my phone, data, talk and text work fine. When I place my sim in her phone, no data (this is the replacement sim they sent me).
Straight Talk tells me the problem is with my phone, but as I did the troubleshooting mentioned above, this seems unlikely.
 
It sounds as if many of us are having very similar problems.

My Nexus 4 has been a glorified, and overly expensive alarm clock for probably at least 2 months now (don't know the exact date of when it started cause the phone is on WiFi almost all the time and well, I don't receive many calls). I can't get anywhere with this problem. I just got a new SIM card from them as a last resort and today was a blast cause their systems can't recognize the SIM serial number either on their website or on the phone. I tried their web-forum, and what a waste of time that is... I was on hold trying to speak to an activation representative for a ridiculous amount of time and eventually hung up. I guess I'll try again tomorrow. However, the SIM in my phone still has the same problem as my current one does.

Back-story: When I signed up to Straight Talk (T-Mobile SIM) back the end of February with my Nexus 4, it quite simply kicked ***. I had great coverage for voice and text and the data speeds were really fast... It worked fine for a few months... Fast forward, I don't use the DATA all the time, as when I'm at work or home, I have WiFi. I did not realize the problem with data right away due to this. However, signal kept becoming a real problem, to the point where I could not even make calls and nobody could hear me and calls would drop constantly, so I started to monitor the phone. Ever since whatever has happened, the signal meter on my phone no longer turns blue. If it has signal at all, it's always grey bars (meaning absolutely no data). Problem is, most of the time my phone is telling me that I have absolutely NO network what-so-ever (Selected network unavailable). First thing I did of course was try to fix it myself, reset APN settings, searched the web to no-avail, etc... Great. I've called them many times... The phone is fine, I've tried it with other people's SIM's and it functions as it should. They tell me everything looks normal and fine on their end and cannot explain why I have zero network and when I do have any signal at all, it's poor and there is ZERO data coverage... I'm getting real tired of this... Whoopty doo, they gave me a free month with the replacement SIM, but it seems as if my problem is not changing. Putting the new SIM in, signal exhibits exactly the same behavior...

Is it just a problem with their service and the Nexus? It's baffling my mind, to be honest. I need a functioning phone again... This $350 alarm clock is not entirely necessary.