catalina - can't change name of bluetooth device

in catalina, i can't change the name of my mac keyboard and mouse. They've been moved from another device (unpaired from the previous device) but the old name sticks. After renaming in System Preferences, it appears that the change has completed, but quitting and reopening System Preferences show that the names revert. I've tried pairing/unpairing and changing the names of this keyboard and mouse (both apple wireless) on 2 different systems - a mac mini and a 2016 MBP: both running 10.15.5