Same issue here
Same issue here, Just connected a shelly 1 without issues, (several other shelly 1 & RGBW2 in operation without issues only Door/window 2 not possible to connect.
app is reporting device is connected, but does not offer the possibility to add the device to a room / connect to cloud.
If I connect to the device with the AP, I can change the wifi credentials, I see the device connecting to my router but than it disappears.
Lost already 8 % of battery power over different attempts
...If I connect to the device with the AP, I can change the wifi credentials, I see the device connecting to my router but than it disappears.
...
That's normal!
Shely DW goes in sleep-mode to save the battery.
If there is anything to transmit (Open, Close ...), the shelly wakes up,, connect to your WIFI, send the data and sleep again. 
Welcome to the forum @all of users in this thread. 
That's normal!
Shely DW goes in sleep-mode to save the battery.
If there is anything to transmit (Open, Close ...), the shelly wakes up,, connect to your WIFI, send the data and sleep again.
Welcome to the forum @all of users in this thread.
I have the same problem as the user Bekovan, which however is more complex than what you understood:
it's true that he was surprised because the DW2 sensors was disappearing from his network, and you correctly explained it with the sensor going in sleep mode.
However, there was a second more important problem (which Bekovan apparently solved because he didn't write anymore) which is my own: I successfully added the DW2 sensor to the app (with both confirmation from the app and visibility in my network) but when trying to add the sensor to a room previously created, no sensor appear and the list is empty (regardless the sensor is in sleeping mode or awake).
I repeated the process for two different DW2 sensors and also for a Motion sensor: no one appear in the list of device included in the WiFi network so no one can be added to a room.
How can I fix the problem?
Thanks in advance
