I’m going to be homeless please help

My wages for 8 months were 4x my actual earnings due to my bosses book keeper making a wage mixup mistake. I have bipolar and depression so I work for a logistics company a few days a week earning £50. HMRC believe I have been earning £180 and have now sent me letters to retrieve the apparent over payment of 1600. My rent is in arrears 900+ and I have to pay 1500 to my car finance company who 2 weeks ago took my car (i surrendered the vehicle) and now I'm due to be homeless. The book keeper was initially helpful and was prepared to solve the problem made by her, but last week she told the boss that she will no longer do his paperwork nor write the letter head that would solve my problem. I have been to the council and provided the true wage slips but they cannot be accepted as some are hand written I'm pretty much done for. I have applied for hundreds of loans the past few weeks with no avail since i now have a black marker on my credit record for my car finance etc. My credit record in December was 516 and is now 120 due to everything piling up on top of me. I have been too ill to work and my boss is still paying me despite not being in at all but it' not enough.

I really need help and haven't ever asked anyone for help with money before but I'm beyond what I could ever fix myself.

Kind regards.

Lee.