Hello! I'm a high school bassoonist that has been playing for a few years now. My upper range and lower range is perfect, but the E and F in the staff are very flat (like 15-20 cents). I can play a c 2 ledger lines above the tenor clef and a low B flat both in tune, but not E and F. Any tips to raise the pitch? I have already experimented with changing my embouchure, with no luck. I read something about clipping to tip of the reed, but I'm very apprehensive with scraping/clipping. Thank you for reading!

Assuming bassoon is sealing well it's often due to reed being too soft. Make sure wires on reed are tight. You could try squeezing 2nd wire from sides very slightly to stiffen reed. Be very careful. You will need a mandrel and pliers with no serrations. If you do this you might need to close the tip down using the first wire.