Sonoff mini R4 detach relay not working

[trossachs1]

I have several sonoff mini R4 switches installed in my house. I was previously able use use the detach relay toggle either manually or via automation. However I have just noticed that the toggle switch no longer works. When I toggle the detach relay function 2 seconds later it toggles back to original setting and I see no change in the on/off mode in the eWeLink app. If I toggle the detach relay in eWeLink it updates in HA.

Has anyone experienced this or offer any advice that will allow me to find what the problem is?

Thanks