Chapter 13 dismissed for lack of payment...

I filed chp.13 in 2005. At the time my husband was making very good money,he was paying off a 401,since then he was injured on the job and let go. He has another job, but is not making half of what he made before.I have been sending payments every month to the trustee.I got a letter that said the case would be dismissed,lack of payment. I called and they said that I should have been paying more since my husbands 401 has been paid,but I do not recall receining any amedment.I check my ledger every month and they have never said that I was behind. So what are my options with out getting my job involved(I would rather keep sending my payments). I don't want to take a chance of losing my job if they find out that I have a bankruptcy.