I hope I am posting the right question in the right section. I just got back my scans from my first medium format film. These are shot with a Yashica Mat, Kodak Portra vc400, expired 1 year ago. All the shots have a straight line on the right size. Not sure why? Trying to figuring out if it is caused by the lab or the way I loaded the film. The Yashica Mat has a gear on the up take spool and pressed against the roll as you shoot.

Here is the set of the photos. I cloned all of them out except one shot to show the location of the straight line.