I have a similar problem. Connecting and setting up Shelly via Shellys WIFI goes without problems. Next connection of Shelly to the home WIFI also works.I can see Shelly on the network (I have tried DHCP and static IP). But subsequently I can no longer connect to Shelly. The browser detects the Shelly page, but no data is loaded and it ends with a connection error. The Shelly cloud app does the same. It sees the device, but no pairing occurs and ends up with a connection error. I've tried hard resetting and reconnecting several times and still the same problem.