Caveats: This is a Prusa based forum, you may get more precise help from a Bambu forum.
I do not know that particular printer so all below is based on general principles.
You have a classic 'Blob of Doom', search here for that phrase to see how others have dealt with them.
Before doing anything, look at pictures of a clean extruder and note the position of everything that is currently hidden, if you damage them you will have to buy replacement parts.
To remove it:
Raise the nozzle temperature to the printing temperature for the filament in question and allow it to heat for several minutes.
If you are lucky you will be able to prise the blob open - more likely you will need to add heat from outside with a heat gun to aid the softening, sometimes it's worth using a soldering iron to carve chunks off the mass.
Use needle nosed pliers to prise this away; remove it in parts if it won't release cleanly.
Once you have the worst removed you decide whether you need to disassemble the extruder to get at all the blob or perhaps you can clean up in situ.
After the cleanup there will be overcooked filament inside the nozzle so at least a purge and probably a cold-pull will be necessary.
Cheerio,