Hi Erik,
I see it’s your first post, welcome 
For every app there is a specific topic, this can be found in the bottom section of the app in the homey appstore or by searching the forum.
In this case, this is the one: Somfy Tahoma & Connexoon (v2.1.2)
Please ask the question over there to Adrian Rockall. (you can start the question by using the @ sign, followed by Adrian_Rockall).
Also provide more info:
Which Homey firmware, which Somfy app version, do you have OAuth on or off.
Check the log file of the app and post a screenshot of the error message.
@moderators Maybe the question could be moved and this topic closed. Im not sure what the right procedure is.
