Self Assessment: Late tax return Daily penalty reminder

Hello, I've not been trading/self employed for nearly 2 years now. Yet for the last few month, I've been receiving late penalty notices for not filing my self passement tax returns. I've rang up many times. Every time I get passed around and confused answers. Some say I don't need to do anything, some say I still need to do my self assessments. Some say they have filled things out for me and should be sorted. I was told to send a letter about my position and try to dispute the penalty notice. I've done that but nothing has happened. My company's has been dissolved for over a year now. I'm not sure what I'm supposed to go. The gov website is a maze or information with links that take you in circles. The letter now says i owe £300 and will incur £10 a day. I've only just received the letter and it says the extra charges started a month ago. I have no idea what to do and i definitely cant afford these charges!

Hi 

I'm sorry that you've received conflicting advice regarding outstanding returns and penalties.
In order for us to confirm if anything remains outstanding, and to advise you further, we would need to access your record - contact us by webchat or phone via Self Assessment: general enquiries to allow us to do this. 

Thank you