Is it legal for a mortgage company to do this?

I was put on a trial payment for a modification and signed a contract that said if I submitted my paperwork and made the 4 trial payments on time it would be finalized. After making the 12th payment and having complied with everything they kicked me out and are putting my house in foreclosure, with the difference between the reduced trial payments and original payments tagged onto the principal. The excuse they are giving is that the difference between my old and trial payments have aculated above the threshold but it's their fault they let it sit for 8 months past the trial period while they told me to wait and they did nothing until the threshold was exceeded. Is it negligence or illegal of them to have just sat on my file until it got kicked out? The underwriter is calculating everything WAY WRONG showing I'm negative $8,000/month which is laughable and obviously an error but they talk over me, are rude and will not listen to me when I tell them they are way off and wrong and will not attempt to correct anything. Can they do this from a legal standpoint, considering it is a government loan they got $80 billion from the government to help with the cost to provide the loan yet are obviously doing it all wrong and scandalously? Is it worth putting my mortgage payment now that I'm in foreclosure into an attorney or do you think he can't help?