I found the problem with my google/EWE smart app connectivity (unable to add Smart We Link app)
I have been struggling to re-connect my Sonoff devices to my Google Home app always getting error : "Couldn't update the settings. Check your connection"
It turn out I have a problematic 4ch Pro, I have multiple 4ch pros with all the same firmware ((Firmware PFS-B04-GL) and setup (network enabled, same naming convention....) but just the single one breaks my google/ewe sync,
hope this helps