It would help if you provide the info needed to match up the layout, portal, and fields to the relationship graph that you uploaded.
One possible issue that you can quickly check is to enter layout mode and try moving this portal a few pixels. If the Sub Acct field does not move when you move the portal (and the others do), then this field is not properly "contained" by the portal. Drag it away from the portal, release the mouse button, and carefully drag it back. Do not release the mouse button until the borders of this field a fully inside the borders of the portal row.