Next years tax?

Hi, I had to become self-employed last year and filled in my self-assessment about 6 months ago. I just received a letter saying I have 60 days to pay £4000! I don't know why I'm only hearing about this now and why I have a short time to pay. Every time I logged into my tax account this year there was a box saying "your taxes are up to date, you have nothing to do/pay" I have been using food banks this winter and I'm currently going through an autism diagnoses. I have spent months with doctors and therapists and getting a letter threatening me to pay all that money in such a short time is utterly destroying. I don't even know why it's such a high amount, or why I have to pay it before I earn money! This seems so insane and its crippling me. I'm too scared to eat, or turn any power in case I get fined even more money in January. Please make this stop! Please please please

Hi,

You will need to contact our Self Assessment team so we can check your account.

Self Assessment: general enquiries

You can also get help with time to pay. 

How to pay a debt to HMRC with a Time to Pay Arrangement

Thank you.