Product: Student loan

I 'm writing to file a complaint about Navient ( formerly XXXX XXXX ) for erroneously raising my interest rate on a fixed-rate loan. I XXXX college XX/XX/XXXX and XXXX school XX/XX/XXXX, and have student loan debt from both. XXXX XXXX holds some of my grad school loans, and I 've had a good experience with them. Unfortunately Navient holds some of my grad school loans, as well as my XXXX loan. I have consistently had a bad experience with this company, but am writing to complain about just one very specific problem : they increased my interest rate when they shouldnt have. I 'm on an income-based repayment ( IBR ) plan, since I 've always worked for non-profits or city gov't. I have to re-certify every year for my IBR plan, and my recertification comes up during the summertime. I pay all my student loans through auto-debit from my bank account. 
In XXXX, XXXX, and XXXX XXXX, Navient correctly deducted two separate payments of {$24.00} and {$120.00} from my bank account for my XXXX and XXXX student loans. I re-certified for IBR. In XXXX XXXX, Navient deducted the wrong amount from my bank account. On XXXX XXXX, XXXX, Navient deducted {$840.00} and on XXXX XXXX, XXXX, deducted {$74.00}. This is because they erroneously returned me to a standard repayment plan, not IBR. This was their mistake, not mine. My income qualified me for payments of {$130.00} and {$13.00}. I called Navient and told them of their error. They said they 'd refund the money to my bank account. They did. On XXXX XXXX, XXXX, Navient refunded the {$840.00} payment to my bank account. ( Later, on XXXX XXXX, XXXX, they also refunded me the {$74.00}. ) In XXXX, Navient started deducting the new, correct IBR payments from my account : {$130.00} and {$13.00}. The same payments were deducted in XXXX, and XXXX, etc. I thought everything was fixed and back to normal. However, I noticed a new problem : Navient had increased my interest rate! This is a fixed-interest rate loan. I called them about it numerous times between XXXX and XXXX XXXX and thought the issue was finally resolved. Navient claimed that my account was delinquent, which allowed them to raise the interest rate. I asked how or when it was ever delinquent, since my payments get deducted automatically every single month from my bank account. They claimed that because they had refunded me the amounts that THEY INCORRECTLY charged me, my account had become delinquent. I had to repeat the story over and over, to various staff who I called various times, of how Navient had charged me an incorrect amount, and that was their fault, and they offered to refund it to my bank account, which was the solution THEY suggested, and I should not be punished or considered delinquent because of their error. I never refused to pay my loans, I never made a late payment, because I was on auto-debit. I merely asked them not to charge me an incorrect amount! I ca n't tell you how frustrating it was to repeat the history over and over every time I called them. I dealt with so many incompetent staff. I thought the issue was finally resolved based on the last phone conversation I had with them about it. My loan payments continued to be deducted automatically every month, to this day. Every month I check and make sure the correct amount is being deducted. However, just recently I decided to give my account a closer look. I realized they had never lowered my interest rate back to the correct amount! They were still charging me 2.625 % instead of what it used to be, I believe 1.625 %. I called Navient again on XXXX XXXX, XXXX, and spoke to someone for 42 min. about this problem. He said he was unable to resolve it himself, but would send an email to someone about it. I asked if he 'd CC me on the email, but he did n't. He said I 'd be refunded all the extra money I erroneously paid to Navient due to them overcharging me and increasing interest rate.