I had a similar problem when I set mine up in a new location after upgrading from version 2 to 3 so I could be closer to the flow monitor. That moved the Rachio from inside the house to outside on the side of the house away from my Wi-Fi router. I simply put a range extender inside the house in a window near the controller, and I have had no problems since then. I will say that I have put the Rachio and other similar things like my Nest on a network separate from my main network. This “services” network then does not compete or communicate with my other computers, etc., but it does have access to the Internet. In other words, it is a guest network. If you do that, it is important when setting up the Rachio that your cell phone with the app be on the same network. Once Rachio is set up, you can communicate changes from anywhere and from any computer with Internet access. Hope that helps.
