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So please take everything I say with a grain of salt because without actually having the printer in my hands I can only diagnose so well; having said all that:
If you remove the fan from the heat sink you will see two (2) small hex head screws. If you loosen the bottom one a little bit you can remove the hotend from the heat sink. The hotend will consist of a heater (red wires), a thermistor (white wires), a heating brick, nozzle, and stem.
Hold the brick with pliers or a wrench and remove the nozzle. GENTLY remove the stem (this stem is not something I have been able to find a replacement for). Take the nozzle and stem and bake them at 450F for 30 minutes to loosen or possibly completely melt any filament clog.
Reassemble. When you reassemble you need to make sure to tighten the stem in first and then tighten the nozzle. If the stem is not tight enough, material can be forced out of the stem end of the brick.
I am assuming you are using PLA filament. If you are using PLA, 450F will pretty much eliminate your clog. If you are using ABS, please be aware that ABS is HIGHLY toxic when heated to its melting point and shouldn't be done in your kitchen oven. I have not used other types of filament and as such have not bothered to assess material safety standards.