Trying to Register a device node ST B-L072Z-LRWAN1 on Iot-lab.info

Hi!
I am using a device ST B-L072Z-LRWAN1 in an experiment setup on the iot-lab.info.
I am trying to register this device for the first time as a device in TTN . So I first created the application and then I created the iotlab node from the TTN webportal. After that I tried to connect the device from the iotlab using the loramac commands . “loramac join otaa” but the answer of the system is →
Join procedure failed!
So I suppose that device is not correctly defined or something else is missing. I have inserted and initalized all the deveui , appeui, appkey fields. I have not defined any gateway since I know that in iot lab there is a gateway very close to the boards. So what is wrong ? Can you please help me . As a further info I do not see any data in the “data tab”. Thank you very much for the help. Bye