Interior door that does not fit

[Tugge10]

Hi, I bought Hornbach interior doors with old standard dimensions for my apartment that don't fit. The measurements of the previous doors I had also didn't match with the old standard dimensions. I realized this when I got home. I thought I could sand so the height fits. Any carpentry tricks? As you can see in the last picture I attached. Then the lower hinge is not completely 100% in the door leaves. Should I perhaps adjust the door leaves that are in the frame? What advice and carpentry techniques do you have to offer?

 

[Dan_Johansson]

If I had to guess, I think the cutout in the door frame is part of the ventilation (i.e., air should be able to move from one side of the door to the other, even when it's closed), if you remove it, you are likely to impair that function....

 

[Tugge10]

If I may guess, I think the cutout in the door frame is part of the ventilation (i.e. air should be able to move from one side of the door to the other, even when it is closed), if you remove it, you are likely to impair that function...

Mm, but I'm not going to remove the whole thing, just sand the arch-shaped parts so that it doesn't go downward but is straight at the top. So it becomes a fully straight frame. If you look at this picture, it's like arches on the sides.