Can'tget gear shift into any gear while engine running

Hi, My 1999 Dodge 2500 Diesel 4x4, 5 speed 105,000 mi standard transmission had its clutch replaced last fall at dodge dealership. They machined the flywheel and installed new clutch pkg including pressure plate,bearing-clutch release,bearing-pilot.
I drove the truck 30 mi to my home then 9 mi back to nearest town and parked. When I got back into truck it would not go into any gear. I called AAA and had it delivered back to dealership. They couldn't
find anything wrong but recommended clutch master/slave as preventative maintenance. I OKed the work and drove the truck home and stored for winter. This spring It acted up again and I took back to dealership.They couldn't find anything wrong but replaced the transmission fluid to see if undo amount of metal in the fluid but found nothing. I drove home
and around a few days. Now I have to put in 2nd gear start engine and drive I can shift to 3rd gear while driving but not 4th nor can I downshift. Once I shif into neutral I have to coast to side of road stop engine put in 2nd , start engine and drive. When I'm stopped w/engine off and put into reverse then start ingine and clutch is deprressed it still wants to backup a littlte. I plan on taking back to dealership but can you diagnose.

Russ