Product: Student loan

I had been on an IBR payment plan based upon my previous employer. My payments were between $ XXXX {$20.00} a month. I reapplied for an IBR my account came up for renewal. I received an email stating it was time to renew my IBR repayment plan and I immediately submitted all documentation. Upon submission I noticed a few days late that I had an outstanding balance that was due. I called and no one could tell me what the balance was for. Im finally representative explained to me that whomever setup my payment plan didnt do so for a full year, but only for 11 months which is why I owed the amount. I was never told this, explained that there were only 11 months, nor did any documentation received state that. I had been on repayment plans before for my student loans and they were all for a minimum of 12 months. I feel like this was done intentionally. Second, I had began working for a different company XX/XX/2018. When I applied for the IBR my repayment was about {$200.00} a month as the company said my income had increased by more than {$16000.00}. My income went from {$34000.00} annually to {$45000.00} but since my taxes have my adjusted income for my previous employer at around {$29000.00} and no adjsted income for the new income yet, including the few months at my previous employer, it looks like I received a {$16000.00} increase. The representative that I spoke with acknowledged that was the issue but said there was nothing that could be done. I advised that 1. ) I would not work a full year with my new employer prior to tax season, 2. ) my pay increase was only about {$10000.00} more a year, 3. ) i was told they could not use my adjusted income until I file taxes next year so even though my repayment is based on an incorrect number there is nothing they can do until my income tax is filed. I was advised by a representative in XXXX of 2018 to consolidate my loans as that should drop my payment low enough since they could not make adjustments for 1 ) not working a full year at my new employer, 2 ) not factoring in the lessor income received the first almost 5 months of the year, 3 ) not factoring my expenses for the month including child care, 4 ) not taking into consideration that I receive governmental assistance to support my XXXX small children as I am a single mother ( my children receive XXXX assistance for food and XXXX Medicaid for medical benefits ), and 5 ) they wont factor in adjustments that will affect my income. I began the consolidation process and was told it would take up to 60 days. I monitored every update via the Navient app. My request was approved in a little more than 30 days however my new payment was due within less than 2 weeks after approval. It was all finalized and approved around XX/XX/XXXX and my payment was due XX/XX/XXXX. This brings me to customer service. 
As soon as I saw this I immediately sent an email to customer service on XX/XX/XXXX. Over a week later, 2 days before my due date, I received another generic response that barely addressed my concern of the short notice of making the payment and their response was wel after the due date. The reply does not even contain the original message. This seems to be recurring. I have submitted several requests, questions via email as paper trail and proof seem to be the only thing that holds up and I have constantly received generic responses that do not address my concerns thoroughly and are responded to so late that I forget the original request. I can not even reply to the representatives response. 
I followed the generic response of looking into repayment plan options but I am not eligible for any of them. This leaves me at square 1. I am very irritated with all of this. I will essentially have to make the large payment until I file my taxes in order for my adjusted income to be considered. I can not afford to pay anything over {$50.00} a month and feed myself and children. I would have to sacrifice food/gas in order to pay my student loan amount listed. If that is my choice food/gas will always win as I have children to care for. I do not know what to do. I can make the payment in the amount I can afford each month but I will always have a balance forwarded. And Im still trying to understand when did the payment plans/options go from 12 months to less than 12.