I submitted my self assessment last year (2016 - 2017) a day or two before the deadline but I'm 90% sure that I used the paper form, not the online form. I have no idea why I did this, but I have a distinct memory of filling out the paper form (possibly because I think you get an extra day or two of grace when sending it it in by paper so close to the wire?).
When I logged in to do last year's SA I saw that they thought I had NOT submitted my 16/17 SA and rang them and they said yeah, before you can appeal a fine (£1k!!! and I didn't even owe any tax!) you have to submit the SA. But I didn't. Anxiety, apathy, ostrich syndrome etc.
I went to do it online today though, and all my info was there! All my data and figures for 16/17 was already in the form, all correct for my calculations (I still had the spreadsheet). It just wasn't submitted.
So WTF? could this be an error on their part? Did they get my info, input it and then not hit submit THEMSELVES?
Or is that physically impossible and I MUST have done it myself and forgotten to hit submit.
Obv. it's all 18 months ago, but I was SURE I had done it by paper.
Sorry for the essay, I'm just confused, and naturally I can't get through to HMRC and naturally I failed to sufficiently identify myself to view my online account.