Hi
Delete the app. Reboot. Change phone language to English. Reboot. Install the app. Then you should be able to login.
Do NOT use any French accents on anything (especially not area names). We have had report of Danish, German, French using their language characters to mess with the app. We already reported it to @Yarbo-Forum and they said they would fix this.
See also this thread: Map disconnected error - #2 by Micke