Can't change the filament in Ender 3.

I' ve got a Creality Ender 3 which was working very well until today, but this morning I've found a problem that I don't know how to solve. Last night I left my Ender printing a project and this morning I've found that only half of the project had been printed and the filament coming from the coil was cut. So, I thought that I should put the filament again inside the tube that goes to the hot end, but I can't do it because when I have slided 3 cm. into the tube, it collides with the remaining filament that is already in the tube. I can't remove the rests of that filamente because I can't reach it in any way that I can think of. Additionally, I think that the hot end is kind of stuck, because if I start a new printing, the hotend starts moving but no filament seems to appear. I don't know what to do right now. Any idea what I can do? Thanks in advance.

sounds like you may have a clog in the nozzle or bowden tube. disconnect the tube from the extruder, preheat pla end option in the menu, then when at temp, disconnect the tube from the extruder and also remove the nozzle. Nozzles are cheap, so may as well replace that while it's out, but stick a pin through the bowden tube, if it gets stuck, it's clogged. if not clogged, you'll be fine with replacing the nozzle, if clogged, you may be able to get away with cutting the clogged portion off, or if too short, replace the tube. the tubing most are currently recommending is capricorn ptfe