GarageBand records my singing slightly flat -- help!

I'm on MacOS 10.15.7, GarageBand 10.3.4. I'm using a USB Blue Yeti mic. When I record myself singing, GarageBand records it slightly flat. I've checked Audio/MIDI Setup and the Blue Yeti is at 44,100 Hz. (I tried it at 48,000 Hz and it was worse.) Can you help? Thanks!