Btw, can anyone explain to me what was wrong with poll tax?
Yes. At the time I lived with my parents and I was on a YTS scheme earning £35 a week. When the poll tax came in, my dad got a bill, my mum got a bill and so did I. There was only my dad who earned a 'proper' wage and he was self employed, so his earnings differed, my mum didn't work and looked after my younger siblings. The bill was more than I earned a month (just for myself), so in essence the government expected my Dad to pay the bill 3 times and we couldn't claim for any help and I suspect a lot of other families felt the same.