Dashboard image not refreshed

So I got a battery video doorbell 4 for around two months. Previously when I open the app every time the still image on the dashboard will refresh to a new image taken immediately. But starting from today I notice that the image on the dashboard would not refresh when I open the app. It would only refresh when something is triggered (e.g. open live view, motion detected, someone ring the bell etc).I just googled this and found that someone mentioned about similar problems in the US forum. Is this a known issue? Any way to fix it?