Is there any conflict between Hyperpixel and Pi 3 BT?

I’m a happy owner of a Hyperpixel.
It works well with my raspverry but when I tried to pair a BT keyboard, I discovered that nothing seems to work.
The command hciconfig has empty content.

 $ hcitool scan
Device is not available: No such device

 $ systemctl status hciuart.service
● hciuart.service - Configure Bluetooth Modems connected by UART
   Loaded: loaded (/lib/systemd/system/hciuart.service; enabled)
   Active: failed (Result: exit-code) since Sat 2017-12-23 21:12:00 UTC; 1s ago
  Process: 432 ExecStart=/usr/bin/btuart (code=exited, status=1/FAILURE)

I don’t know where to search…

Do you have anything like dtoverlay=pi3-disable-bt or dtoverlay=pi3-miniuart-bt in your /boot/config.txt file?

Nothing with bt mentionned.
The only overlay is :

What if you fire up bluetoothctl;

sudo bluetoothctl
agent on
pi@Dobby:~ $ sudo bluetoothctl
[bluetooth]# agent on
Agent registered
[bluetooth]# default-agent
Default agent request successful
[bluetooth]# devices

if anyone has an idea, I can try whatever needed. It looks so great to have Hiperpixel and this keyboard.

This Rii keyboard contains a bluetooth dongle and it works.
The only thing that is not working is the Pi3 embedded bluetooth