Nationstar Mortgage Fraudulent & Erroneous Billing on Fixed Rate Mortgage Just took over from BOA doing same thing Lewisville Texas

I just received notice last month from BOA that NationStar had purchased my loan from BOA.  I am current on mortgage but since 2008 BOA has tried and has successfully harassed and bullied me.  I have a fixed rate mortgage.  BOA has made my escrow negative siffoning money out of escrow in the "name of insurance" I already carry.  My escrow starts off negative according to BOA every January.  The numbers don't add up and I have not received support from Texas Attorney General who I have copied since 2008!  The office of the comptroller of the currency is not helpind either.  I am exhasperated and need someone to step up to the plate for me.  I am intelligent, thus I have kept house up to now but NationStar is giving me a "BAD" feeling in only 1 month.  I sent proof to them that my installment is 730, all insurnace declaration pages, etc... but they did not acknowledge this and instead sent statement for the next month saying I did not pay what I owed in full last month, thus I am being billed for late fees I don't owe, as well as an inflated installment of 880 and 900+ if late!  Their note back to me is making me nervous I have 2 children, single parent, and cannot lose my home.  Please someone help!  I have fixed rate, am current, have proof as I sent paperwork in certified as I thought something very strange with the transfer of note from BOA out of the blue to NaitonStar and no official documentation just a slip of paper in my last bill from BOA.  I knew it was not going to be good but it seems eerily worse than I imagined.

I am beggin for help.  Please!