Product: Mortgage

XXXX XXXX sold my current home equity loan to SLS Specialized loan servicing and payments are to be sent  directly to them by XX/XX/XXXX. I have been paying ahead with my payments with XXXX and have all the monthly statements to show the dates and amounts paid. My next payment due date isn't due until XX/XX/XXXX. On XX/XX/XXXX I received a call from SLS to verify the information they have on file they need to validate due to the mortgage transfer. Immediately I had advised them that my payment amount is incorrect and the due date is wrong as well rep informed me that since it has only been a couple of days to give it time to update in the system. I told her I was not going to wait and needed the contact to send the dispute to the rep gave me the email address XXXX and was given log on instructions to go online and review my loan. In which I found the following errors ; my payment amount was for {$520.00} when my payment amount is only {$440.00}. The due date showed next payment due XX/XX/XXXX, I have been making additional payments to XXXX prior to the transfer I pulled my loan information from XXXX  and the statement showed no payment due for the due date of XX/XX/XXXX that is cause I have been paying ahead and the loan balance was {$97000.00}. I made a direct payment to SLS on XX/XX/XXXX this payment was applied to the XX/XX/XXXX next payment due date. I called on XX/XX/XXXX and spoke to a representative XXXX teller # XXXX I informed her of my concerns and she stated that an email was never received I told her I emailed the email address given to me and also used their message portal and got a response to fax the documents as they are unable to accept attachments from their site. I faxed a copy of my note, deed and XXXX   mortgage statements from the inception of the loan. I also included my personal tracking log of the payments made that matched with the info on the statements. I asked why my payment increased I was aware it was a HELOC but the rate had not changed from the previous month she said it was because the XXXX payment was prorated. I told her that my loan is current and to prorate payments? why when I am charged interest daily? she said to send the information to the email again and that she would call me the next day to confirm receipt. I never received her call. I have emailed this company regarding this issue on XX/XX/XXXX, faxed the documents needed to correct and update my loan information. I called on XX/XX/XXXX have not gotten any type of response from this company other than the payment I made to them directly on XX/XX/XXXX was reversed and applied to principal. Also, the loan balance had increased by {$970.00} on the statement it states {$520.00} finance charges and {$440.00} past due amount. I supplied the note and deed because they had the incorrect first payment due date and also the closing date on the loan. Today I have been on hold for over 3 hours and have not been able to get anyone to assist me regarding this matter. Are they allowed to charge me finance charges when my loan is due and also because the loan was transferred? Can they add a balance to my previous loan balance? when I did not take any draws but it is related to amounts they claim is owed. I would please like to submit this complaint in regards to their process and that they have not contacted me as informed by the agent, nor have they responded to any of the correspondences I have been sending since XX/XX/XXXX.