Just discovered this week, the wifi on SM2 will only connect on allowed wifi channels that are permitted in China. Whereas in the west etc much more channels are allowed.
Your wifi router by default has a Auto function to change channels depending on interference, and if you have more than one wifi router in operation you will most likely manually select different channels to avoid conflict.
So, if by Manual or Auto means your wifi router goes onto a channel that is not permitted in China, no matter where you are, then the SM2 will not connect. See the list in the link above, and set your wifi router to a channel it will connect on. O, and the camera only works to Luban by wifi connection, so will explain that one too if the same issue.
There is a free “wifi analyzer” app for win 10 that will scan to tell you what channels are being used. Look for your SSID, then you will need to know your wifi router IP and log in as Admin to make the changes.