Filament stuck on print core 1

[privateme 0]

Hey all,

I am a student at a school and I help manage the 3D printer we own, an Ultimaker S3. There is filament stuck on print core 1 which I can't get off. How do I get it off?

[Dustin 175]

There is a guide for dealing with this on our knowledge base 🙂
here: https://support.ultimaker.com/s/article/1667412700999

Additionally it looks like you don't have the silicone nozzle covers installed. 
Its recommended you reinstall that as it helps prevent how bad this buildup can get.
It also helps with better temperature control when doing dual extrusion prints.
You can learn more about the silicone cover here: https://support.ultimaker.com/s/article/1667418049456