Meopta Opemus 7. 6x7 mount smaller than film frame

In the club darkroom there is a b&w Meopta Opemus 7 enlarger.

First time trying to print from a 120 negative a 6x7 frame, I noticed that the frame from the negative mount was a bit smaller than the frame of the negative and as a result a part of the image was cut out. Moreover, I couldn't move the negative up due to the two drivers for the alignment of the negative.

I know that this enlarger is suitable for 6x7 frames. Thus, is it normal that the size of the frame of the negative mount is smaller than the size of the image?

Is there something that I can do? under these circumstances I cannot print any full 6x7 image.

You can make your own carrier, glassless or with AN glass, from plastic, MDF, metal or even thick cardboard painted matt black. Or buy a 6x7 carrier for this particular enlarger and file the edges to approx. 63x73mm. Neither should be too difficult or expensive. Have fun! Opemuses are excellent machines, there's lots of them here in Croatia and they're indestructible!