Can someone help me make an adjustment on my VAT return please?

[bramblina]

Last quarter I entered the same figure in box 3 and 4 so ended up with a nil return. I obvs need to adjust accordingly to add this back in- does the difference (ie what I should have paid) need to be added to box 1?

BUT, I also bought a new vehicle this quarter so need to manually adjust the VAT amount and am not sure where to put this.

Never mind I've done it anyway. Just hope it's right...

if the error was under £3000 its below the misdeclaration limit so HMRC do not really care