While cleaning this pen I think I accidentally removed the nib-holder unit (marked in arrow) from the section. Although the nib holder unit has a screw, it was not screwed inside to the section. But, rather pasted to the inside of the section. When I try to insert the nib holder unit, it remains loose. What can I do in this situation? Is this damage irreversible? https://www.fountainpennetwork.com/forum/uploads/imgs/fpn_1597461428__j886_1.jpeg https://www.fountainpennetwork.com/forum/uploads/imgs/fpn_1597461497__j886_2.jpeg