All 5 of my 3B+ no longer perform a USB boot, from USB stick. Problem first noticed where OS was MoodeAudio and a HiBerry Hat was in use. Other similar systems (using diferent 3B+'s with different DACs and/or amp hats have the same problem By experimenting with different OS, including Moode, Buster and Bullseye Raspbian/Pi OS on these three Pis, plus two others which have no Hats, I tracked it down to USB boot not working.
USB sticks have included old and new, and will boot a 4B+ satisfactorily. There are no other devices attached, except USB dongle that supports mouse and keyboard. Power supply is official Pi micro-usb (although I have also used official Pi USB-C.