I have a 2004 Harley Sporter 1200 custom. When the clutch is pulled in, transmission won't disengage. I have done a clutch adjustment, helps but doesn't resolve my issue. Any help out there?

It may not be dissengaging, If Hydraulic, it may need bleeding.
If cable, try more tension.
Try rocking bike back and forth while working shift lever, with clutch pulled in.

Have you checked the adjustment at the clutch removing the derby cover. If the adjuster is too far out the clutch rod won't engage with enough length to separate the plates. Missing clutch rod parts or a bent clutch rod could do this as well. Dirty primary oil can cause sticky plates which makes finding neutral hard.