Product: Mortgage

I have my mortgage with Key Bank. I purchased my home in XXXX and XXXX XXXX  XXXX XXXX was my bank, which is now Key Bank. I had my checking account there also. I always paid my mortgage on time and was paying approx. {$100.00}. per month towards principal. I had my pmts. on Auto-pay each month, to come out of my checking each month. Same bank, easy right? XX/XX/XXXX, Key Bank froze my account with no warning. I had no idea until I went to check that my utility bills were paid ( also on autopay ) and saw that nothing had been paid and my checking account was negative. I called, nothing they said made sense to me, they said they noticed " fraudulent activity '' on my account. My son and I went to speak with a rep. there and found that there was NOT any fraud activity, and the bank rep told me to bring him receipts of my last few mortge pmts. I did, but the info was all in the bank 's system already. When I showed a rep my receipts proving I paid AND it was on time, he looked me in the eye and rolled his shoulders saying : " Anyone can forge documents. '' I could not believe this! It was XXXX, XXXX, XX/XX/XXXX that I went into the branch with my receipts, during pandemic, only a couple people working in the bank. I took my son with me and he tried ... .he got the same answers. They hid it from me by putting it in suspense and telling me they were going to foreclose if they didn't receive the full amount immediately. They began putting my mtge pmts into a suspense file and refusing all the payments to my bills I had on autopay. They started charging me late payment fees, over drawn checking fees, they took all my direct deposits and also my government incentive payments. Mortgage statement said I owed them over {$8000.00}! I called them every month, explaining everything over and over. I closed the checking account so they'd stop taking all my money. I had to borrow the money from my son. I continued to pay my mortgage but they would never apply it until the last of each month. They charged me late fees each DAY on these! I was never late! Never missed any payments! Sometimes I paid at the end of a month for the following month. I was mortified and confused, I was losing my mind! I am on XXXX for XXXX problems and XXXX  problems that affect my health. My husband had XXXX in XX/XX/XXXX and I was not receiving any widows benefits. We were married in XXXX so I would think I would get something. But I was paying my mortgage, and other bills with my XXXX while Key Bank was taking my XXXX XXXX XXXX XXXX each month until I closed them. I had filed complaints with XXXX XXXX 's office, XXXX, and another co. I can't remember who. Then as I was spending every waking hour of my time trying to find every transaction I ever made with Key Bank ( all receipts and house info were in several different boxes stored in various places because our house was gutted and repaired due to hurricanes, leaks in the roof, damage extensive. Then again in early XXXX, more work done - new windows, roof and siding. Homeowners Ins required the repairs because this is a 2 family house. I rent it to my son and his family. ) Key Bank had made some adjustments to my account. I was relieved, thought they had found the initial problem. But no. Started again. So this happened a few more times, then I'd start back in on my receipts. Then it stopped again in XXXX this year, XXXX. Now as of XX/XX/XXXX ( this past week ) they are at it again. They can no longer take my direct deposit, so they add late fees to my mortgage account so when I make a payment, ( which I have been doing in person beginning these last few months on the XX/XX/XXXXXX/XX/XXXX of each month ) they say it's a partial payment and they stick it in suspense. I am at my wits end!! This began as an error on THEIR part and all thru this entire nightmare, I have been, STILL, paying my complete mortgage in full and on time!! What can I do to make them correct this and reimburse me what they took from me?? I had a small amount of my husband 's life insurance money left. I had to use it to pay everything. The creditors whose payments I had on auto pay also charged me late fees, so I had to pay that too, for instance, my heat, electricity, car insurance, etc. etc. and I also had to eat. 
If I knew that they were going to rob me blind, I would have used my husbands life insurance money to pay off my house. I had enough at the beginning of this mess to do so! But that's gone now, also. I only owed {$70000.00}. on the mortgage when this began a year ago. I STILL owe {$70000.00}. because they aren't applying my payments, and still my statements say I owe {$5700.00}. on late payments! 
Please tell me what I need to do.