Cannot conntec to reciever anymore

Just installed a new router Sagemcom dualband (2,4 Ghz + 5 GHz), instead of Sagemcom single band.

After the installation I set the controller back to factory settings and did go through the whole installation process again, without any problem. The controller connects to my wi-fi ok. When asked to connect to the receiver the controller show the right reciever (last six number of the Mac-code) but it cannot connect to the reciver?

Tried to reset the receiver by holding the bottom in fo like +10 secs and it start to flash red rapidly, solid red for a short while and the slow red flashing, just like it says in the manual, but then nothing more is happening?

Can the controller have stored some informations from the privous network, despite I did starts up on factory settings, since it comes up with the Mac code from the receiver, despite the receiver is not connetted to the net work?

Is there a step further back than factory settings, to do a whole new set-up again?

Thanks,
Henrik