You'll have to remove the bowden at one end to get it out - I recommend removing it at the feeder in this particular case. First heat up the nozzle to 180C. Then, to remove bowden from feeder, first remove the horse shoe shaped colored clip that holds up the bowden-holder. Then push down firmly on the bowden holder - this is critical - if it won't go down push harder - certainly don't pull up on the bowden until the bowden-holder is moved down slightly. Once it is down pull up on the bowden tube while holding the holder down. Inside the bowden holder are 4 metal blades - if you do it wrong they will remove a little bit of material on the outside of the bowden and make it so that you can't hold the bowden down next time. 3d printing technology - fdm materials
Once that is out and you have exposed a few inches of PLA you can pull up on the pla from above the feeder at the same time as pushing from below. Or the other way around. Or pull from both ends and try to break it in the middle if you want but that might be too difficult. I's helpful to have the nozzle at 180C all this time.
Once you get the PLA out, inspect the tube for a small piece of PLA just in case - you don't want that binding the new piece of filament on your next attempt at printing.