Product: Mortgage

We are filing a complaint against Amerihome Mortgage, who holds the mortgage on our second home located at XXXX XXXX XXXX, # XXXX, XXXX, Maine XXXX. They are located in California but licensed to offer products and services in the State of Maine. 
In XXXX, they applied one of our mortgage payments to another customers account and have refused to correct this problem after multiple attempts contact them, and promises by managers and employees that this would be taken care of. This is now affecting our credit. 

Following is a history of what has taken place over the past several months : In XXXX we received our mortgage statement showing a late fee and that our payment was not received in XXXX. We called them and after being placed on hold and transferred to multiple people, were eventually told that they would look into it and would call us back they never did. We called again a week later and again were put on hold and the call was dropped. We called back multiple times between late XXXX and late XXXX, getting no resolution. 
On XX/XX/XXXX we reached an account representative and they verified that our payment had been applied to another customers account in error. A manager called us back on XX/XX/XXXX and validated what the account representative found, and promised that she would put in a request with finance to current the error. The mangers name was XXXX XXXX would not provide a last name ). 
Our XXXX statement showed that this had still not been taken care of and we were charged another late fee. We called again and after another hour on the phone, an account representative said that they saw the notes that our payment was applied to the wrong account. This continued for the next few weeks, and so on XX/XX/XXXX we faxed our bank statement showing that all of our payments had cleared to every fax number we could find on the Amerihome Mortgage website, and we heard nothing. We attached the same bank statement to our XXXX payment with a note, asking for this to be fixed. We again heard nothing. 
On XX/XX/XXXX we spoke to XXXX XXXX XXXX about refinancing this mortgage to a lower rate, and were told by XXXX XXXX XXXXXXXX that we had a late payment/ delinquency notice on our account, and that they couldn't proceed with a refinance application until this was resolved. 
We called Ameriome Mortgage on XX/XX/XXXX and spoke to two account representatives. After 2 hours and 16 minutes on the phone, they said that we would receive a letter stating that this was an error on their behalf. The letter was request by XXXX  XXXX XXXX so that we could proceed with the refinance. We spoke to XXXX ( employee # XXXX XXXX. We received a letter on XX/XX/XXXX showing the wrong information with payments made in XXXX ; nothing resembling what we were promised, stating that they are in the wrong and that this was corrected. 

We have no idea how to get this resolved and are reaching out to you. The have acknowledged that our payment was applied to the wrong customers account in error. We have received letters and calls stating that we are in default, assessed late fees, and yet they continue to not fix this issue. We have faxed our bank statement XXXX attached ) showing that all of our checks have cleared. We are truly at a loss. 
Any help and support that you can provide would be greatly appreciated.