Laser 2 jib halyard jammed

Hey everyone,

"Learning" how to get ready for the water in my driveway. Mast is up. All is well. Mainsail halyard moves freely but the jib halyard pulls through only 3-4 feet then jams tight and will not move any further.

I'm assuming there's a too big knot inside the mast connecting the wire to the line, and it's getting hung up on something inside the mast but I have no idea how to get to it to fix it.

Any suggestions?

Thanks in advance.
Doug