Thanks for your help ! but I still can't make it work
I am using this
luup.variable_set ("urn:akbooer-com:serviceId:Netatmo1", "Username", "mynetatmoemaillogin", 154)
luup.variable_set ("urn:akbooer-com:serviceId:Netatmo1", "Password", "mynetatmopassword", 154)
So I use my email to log in my netatmo account and my password.... 154 is the device.