BlueR: Method doesn't exist

Hi,

I'm relatively new to Rust and absolutely new to Bluetooth. Right now I'm playing with the official examples.

$ cargo run --example le_advertise
    Finished dev [unoptimized + debuginfo] target(s) in 0.10s
     Running `target/debug/examples/le_advertise`
Advertising on Bluetooth adapter hci0 with address 00:1B:10:00:2A:EC
Advertisement { advertisement_type: Peripheral, service_uuids: {123e4567-e89b-12d3-a456-426614174000}, manufacturer_data: {}, solicit_uuids: {}, service_data: {}, advertisting_data: {}, discoverable: Some(true), discoverable_timeout: None, system_includes: {}, local_name: Some("le_advertise"), appearance: None, duration: None, timeout: None, secondary_channel: None, min_interval: None, max_interval: None, tx_power: None, _non_exhaustive: () }
Error: Error { kind: Internal(DBus("org.freedesktop.DBus.Error.UnknownMethod")), message: "Method \"RegisterAdvertisement\" with signature \"oa{sv}\" on interface \"org.bluez.LEAdvertisingManager1\" doesn't exist\n" }

The curious point: I've deployed the BlueR project on two boxes, and on one of them le_advertize runs fine. Both boxes are powered with Manjaro KDE; the "good" one is a laptop with integral Bluetooth, the "bad" one is a desktop with a noname USB Bluetooth dongle. The dongle is not dead; at least, scanning from the (Bluedevil?) GUI works, the advertizing laptop is visible.

What should be my first step?

Do the two systems have the same version of BlueZ?

Certainly.

It looks like the trouble has nothing to do with software. On the "good" box I see, among other things,

$ bluetoothctl show
...

Roles, GAP, GATT; none of these on the "bad" box. The dongle is, probably, BR/EDR, not BLE. Am I correct?