It seems that around Feb 8, Tracfone had some type of reporting glitch involving their T-Mobile network customers, and wiped out any accumulated data balances. The problem seems isolated to accounts using T-Mobile,
It's unknown whether all T-Mobile users are affected, or just some. Although I haven't seen reports, I would also recommend you check your data balance if you're using the T-Mobile network on any other Tracfone company, including Simple Mobile, Straight Talk, and Net10.
There is recourse if you follow up. Tracfone is aware of the issue (although they will likely deny being aware of it), and escalations seem to be forwarded to agents that know of it. As a fallback, Tracfone usually responds quickly to complaints filed with BBB and the FCC. If you can document what your balance should be, you shouldn't settle for less than that balance-- get what you can from customer service while stating your dissatisfaction, ask for a transaction reference number, and follow up by filing complaints with BBB & FCC.
We have an affected line on Tracfone T-Mobile, with 2.6GB of accumulated data, which now shows only 10MB of available data. I have screenshots, and will follow up today.
Update: Chat to get back the missing data went about like I expected. At first, the agent said I had used all the data. (Not true, and I told her I had a recent screenshot to indicate that, and that I was aware there was a system glitch causing similar problems for many.)
Then she said I couldn't have had that much data anyway, since it only had 1200mb from the last phone swap. I told her that was also not true since the account had a previous existing balance, and provided a chat reference number confirming my prior balances before swapping to the current bundled phone.
After more checking, she added the proper balance back to my line.
Bottomline-- Tracfone can be difficult to manage, since it's one of the few places where units roll over instead of refreshing with new units each month, and Tracfone doesn't provide account info detailing specific usage. It's really important to maintain good records in case something like this happens.