Rfxtrx blinds

I created a cover device , Blinds T3 protocol, via automatic add.
Using the remote, I can see that HA is receiving the commands, the device icon is changing according to the received commands.
But pushing the Up/Down/Stop button in HA does not do anything.
Looks like, I can receive, but not send.

Or did I forget to do something ?

Some additional info :

rfxmgr says :

Packettype = BLINDS1
subtype = A-OK AC114
Sequence nbr = 0
id1-3 = C1C47B decimal:12698747
Unit = 2
Command = Open
Signal level = 4 -88dBm

HA receives this as :

BlindsT3 / A-OK AC114

The remote says :
AC 123

I am confused.