The bottom 1 -1/2 feet of vertical edge the main sail is not inside the extrusion track on the selden furler unit.
If I understand this correctly...
Any part of the sail tracking cord on the Luff of the sail out of the "extrusion track", it has to be reinserted.
The Foil or flexible tube has a slot in it. [extrusion track?]
All of the Luff cord must be inside that Foil slot.
To fix, you do an almost complete main sail removal, but short of removing the upper and lower shackles.
Then re-thread the Luff Cord, as you slowly haul up the Halyard to retention your luff, and set the swivel tension again.
Jim..