Welcome to the Forum, @msdillydalley! 
It may not be necessary to delete them. I would start by trying a factory reset on one Plug and then make sure you’re doing other things to maximize your success with attaching the Plugs to your new Wi-Fi. I had a frustrating time reconnecting a Plug to my home network last year and wrote about what finally helped me to get the plug on my LAN. More recently, I mentioned a few other things that might help. You could try those things after a factory reset and then attempt to add the Plug with the same name you’ve been using for it in the app.
Also note that if your new home network uses the same Wi-Fi SSID and password as the old network, then going through setup again may not be necessary. Your screenshot seems to indicate that you’ve tried starting setup again, though, so this bit might not apply to your situation.