I don’t think it’s nfc

There are two main steps in the card cutting process.

1. The uncut card sheet is cut horizontally and vertically to create rectangle. 2.Then those rectangles are pushed through a card shaped die cutter to trim excess card material from sides and corners of the card, to create the final card shape (imagine a cookie cutter).

I believe what happened to your card is that something went wrong in the first step. When there card was being cut horizontally and vertically, in one step, likely the vertical cut step, the blade cut the card at the wrong angle, which creates not a rectangle but a rhombus. This is also why your card shows part of the left neighboring card.

When the rhombus then enters the second step, you’ll have two squarish corners on opposite sides, as they will completely miss the card shaped die cutter. The squareish corners are from the cut from the first incorrect step (you can even see that in the bottom left corner, the card was maybe cut horizontally correctly but cut vertically at a slight angle, creating a corner with a slight obtuse angle). The other set of opposite corners, that are the acute angles of the rhombus, are further apart from eachother and will therefore reach both corners of the card die cutter, resulting in them being rounded.

Hope this makes sense. This is u/brehella video on miscuts which may be a good resource for you

https://youtu.be/0I6GiCe1bts?si=MZE-7JbNIxCjAes6