Hey Peach,
A clogging nozzle could be due to a number of reasons!
A few of which you have tried to fix yourself.
I would (if you can) strip down the hot-end as much as you can and give it a good clean! It could be that a small bit of dirt has got into the heated chamber and is blocking the Nozzle.
The simplest way to trying to fix this is to heat some filament up and let it cool a bit, then pull it out!
So for PLA, I would suggest heating it up to 180*C and turn the heat off. Let the hot-end cool a bit (maybe let it cool to 150*C) then pull the filament out of the top of the hot-end. You will know if it has worked temperature wise if there is no stringing when you pull the filament from the top of the hot-end. It should be clean and hardly any wispy bit of melted filament. If not, redo the process and let the hot-end cool for another 10*C.
I would also make sure that the filament is clean and has no dust particles on it. If it has been laying in a locker exposed to the environment then it easily could have accumulated particles.
Its these particles which should be cleared if you use the method I have described above.
I hope this helps and let me know how it goes!!
Thanks,
Alex
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