Free Traffic Legal Advice

Hi any advice. PCN received 80 days after crossing. I tried to pay in July but their system was down - some issues with the whole system. I thought they cancelled due to technical issues. Then received PCN 80 days later. They told me to appeal - I did - then they said I was too late. I am about to do witness statement. I was a bit late but they didn’t mention this on phone. I had become unwell and was dealing with that for few weeks.