Echo Show shows Ring Doorbell 4 camera half of the time

Hi I have a problem, hopefully somebody can help. When I say ‘Alexa show the front door’ the response is always ‘Ok’ but many times nothing shows on screen. I get same problem when I press the doorbell button. I always get verbal notification on all devices. Alexa works on my LG Tv and shows camera every time, the ring app is also working fine. I have tried reinstalling the Alexa skill and I have placed both devices next to my router. It does work some of the time but it isn’t reliable right now. I have a Bt home hub router that is broadcasting combined 5ghz/2.5ghz signal. It appears doorbell is connected to 2.5ghz. So in summary problem appears to be with echo show/Alexa skill or possibly the router. I’m even considering adding a separate WiFi router to narrow the problem. Any ideas ?