Device unresponsive to physical switch, requires power cycle

I installed a shelly 2.5 in a 2-gang box, where it's connected to two lights. I had to fight with the device to get it configured and talking with the cloud, and have had nothing but problems since. The biggest issue is that the device will fail in the open state and becomes completely unresponsive. Turning the connected switches on and off does nothing and I have to cycle power to the device for that functionality to work again.

I had the device connected to the cloud, but it went offline in less than 30 minutes and I can't get it to communicate again. My Wi-Fi signal is strong at the device location so that shouldn't be the issue. While it was connected I could see power draw, the state of each relay, and I could control the relays through the app. It may be related, but when I have the lights on, the lights will turn off for 1-2 seconds and come back on. The frequency seems to be inconsistent as sometimes it happens about a minute apart, and other times the lights will stay on for several minutes without it happening.

During the connection process I did update the firmware, which caused the device to stop communicating and I had to do a factory reset to get it connected again.

Thanks in advance for trouble-shooting advice.

66er, Thank you for the reply. You are correct: this is my first Shelly device.

I have two lights connected to the shelly and the larger of the two only draws 1.2 amps, so the current draw should not be an issue.

I took a look at the beginners tips and couldn't find anything to specify what makes a router incompatible. I'm currently using a consumer-grade Netgear router/AP (AP functionality turned off) and have a Unifi UAP Nano HD for my WLAN. I'm using the 2.4 GHz network for my automation devices. My SSID (broadcast, not hidden) does contain a "-", would the dash be considered a special character that may cause connection problems?

I have tried factory resetting the device and it goes back into AP mode where I can see it when using the phone app and I can connect it to my WLAN. My router is assigning an IP and I can ping the IP (issues noted below), but I can't get it to import into the app and I can't get the the UI in a web browser any more. I was initially able to access the UI via web browser.

I sent a ping -n100 command to the IP address and lost 67% of the packets to the Shelly device. I tried pinging (also -n 100) a few other devices on my WLAN and had no packet loss with the other devices.

I'm not an IT professional, just a tinkerer who has read a lot and played around, so I definitely have some gaps in my knowledge. I could be overlooking something a professional would quickly notice.

Thanks

66er I've actually been meaning to get around to replacing my router. I've got a Ubiquiti Edgerouter sitting on the shelf waiting for me. Is Ubiquiti compatible with Shelly? Also, is there a link to a list of compatible/incompatible routers?

I do have a special character in my SSID, (currently using BAS-LAN) but I'll have to set up a temporary SSID without the special character to test with. Reconfiguring all my devices to a new SSID will not be a small task, so I want to make sure that's the issue before diving into the additional work.