Using a 3rd gen Stickup Cam. After a power outage or wifi disconnect the the app shows a healthy online cam and it also appears that way to tech services. Only way to reconnect is to go thru a physical reset. This is ok if you are home but if you are traveling there should be a way to do this from the app.
I just experienced this same problem with two cameras. I had to disconnect and reconnect the power plug to get them back online.