Telcel Unused Data MBs Lost?

My husband was not able to renew his Telcel Amigo Sin Límites plan on the day it expired. The next day (today) he went to renew his 150 plan, but the local Telcel office was closed, so he went to Oxxo instead. When he got home, he was surprised to see that he only had 600 mb to use -- the number that comes with the 150 plan. All of his unused data is not available. Does anyone know if you can go into a Telcel office and simply buy more mb's to add to your plan? We're headed up to the States for a couple of weeks and will need to have more data.

Okay, I managed to answer my own question -- well, actually I stopped and got answers from the very helpful young man, Pime, who works in the small Telcel store right near the Chapala plaza. He speaks good English BTW. Anyway, it turns out that if a person is one day late paying for their plan, s/he loses all of the accumulated data. You could buy more data, but all data must be zeroed out to do so. Looks like my husband will just have to go in and pay for the 300 or 400 peso plan in order to get the MBs needed for our trip NOB.

Gosh I guess it depends upon the plan. At least in the olden days with the basic PLAN AMIGO. you could carry your old credits forward if you made another payment within a few months of your old expiration date. I do not know about today.