I think some have called that "skip" with the die slipping on strike...Something of that sort...Comes with a shelf-like appearance at the date and occasionally other devices.
Another coin collector had a Looking at this, the verdict........
"it looks like an Edward IV 1st Reign groat of the Light Coinage issue (1464-70). No marks at neck, mint mark crown on the obverse. London mint." 🎉
Happy Happy Happy!!!!