2 Months is not that long for things to get that kind of stuck. Unless that pressure plate mating surface and other areas are really bad shape.
Leaving the clutch pushed it will help till it can be reviewed.
Did you rebuilt/restore that truck or someone else?
If you did. Was the clutch overhauled?
This sound more like you need to have flywheel and plate pulled and looked at.
Turned or replaced and cleaned up.
Here is a decent video of it being done. Very interesting use of bread at the
4:30 mark.
https://www.youtube.com/watch?v=zybh49AXnC0