Lia:
You have chosen the Complex Profile option for the Column. Custom Profiles cannot be smaller than the original Custom Profile it is based on (they can be larger). In your screen shot, the size (261 x 276) in the upper right of the column pop-up list is the original size. You can edit the original Custom Profile (using the
Profile Manager) to be as small as the smallest column you want to use, or create a new Custom Profile again at the smallest size. You can also look at the
Import Standard Steel Profile... command to import a different size column.
You should add a Signature to your Profile (click the Profile button near the top of this page) with your ArchiCAD version and operating system (see mine for an example) for more accurate help in this forum.
David