Poor service

This has been going on for over a year . BOA modified my loan I paid the trail payments was told not to pay until  the final papers approved . Once received the papers began paying payments.  Have talked to numerous people  been told its taken care of but still am getting letters stating foreclosure and  have numerous charges listed as late charges have 30 60 90 days late on my credit report. Have a letter stateting this has all been taken care of and still nothing. They send back five or six checks to me stating  its not full payment when I called and asked why are you sending me back money I was told hun we don't need it. I was told the missing payment was found in a holding account. I was told if I am recording them they will hang up yet every time call they tell me they are recording me. I have many of the conversations the one from the man telling me I promise this has been taken care of the money was in a holding account.  I am so very frustrated and highly stressed not knowing if they are going to foreclose as they keep threatening.  I have letters from them stating  they looked into my complaint and its being dealt with I asked to an appt when they were locally seeing people at the convention center so I could sit down with someone and show all my paper work but no response . I am sooooo frustrated.