Do you know, że… ?
The edges of the plate have been bent, one on the inside and the other on the outside. During unfolding there is a collision of material and it is known, that it cannot be done.
If you right click on the flat pattern you can select Show problem areas. Then the collision location will be displayed in yellow.
A separate topic is the repair of such places, because it can be done in several ways. Jeżeli znasz jakieś fajne rozwiązanie – napisz w komentarzu!