I have used the online site to declare that I have never been self employed. I signed up for self assessment a year ago as I was planning to do child minding alongside university but I didn't end up doing the child minding. I forgot that I had even signed up to do the tax return until I got a letter reminder. At this point I cancelled it online but have since had an email reminder too. I am worried that I will be penalised for not completing the tax return even though I have attempted to cancel it and haven't ever been self employed.