I have an HBot 3D 1.1 printer (it's a CoreXY style printer, newer versions are produced by ZMorph). I think that a filament guide tube inside the hotend got damaged, resulting in decreased diameter, which means I can't push the filament through it. It stops halfway through the heatsink (black marker in the attached photo).
I need some help, I'm not sure how to disassemble this type of hotend. With my Ender 3 which I have at home, I can just unscrew the nozzle since it's simply a hexagonal nut, but here it seems that the nozzle and heat block are one part and I don't think I can unscrew the heat block and the heatsink. I'm not sure what to do.
I'm sure the nozzle itself isn't clogged. I've done some cold-pulling on one end, inserted a thin wire from the other, and examined the insides with a flashlight.