How to Change Bluetooth MAC?

Hi there,
for a small Project I need two Rock Pi 4’s to communicate with each other over Bluetooth LE. After some trying I ran into an Issue: Both Pi’s have the same MAC Address. I found several Forum posts which almost all lead to using bdaddr or hciconfig.
bdaddr -i hci0 (-r) [New Address] doesn’t change anything. In the console output it says that the address was changed. But if I call bdaddr again, I get the old MAC.
Hciconfig is not available on my Pi, since it is not included in BlueZ 5.50 anymore. Maybe it is possible to install hciconfig anyway. But I think there must be an other way than using deprecated Software.

Greetings from Germany
Philipp