I have several V2 and V3 cameras and all of them often get stuck loading the recorded video to view, there are no memory cards in the cameras. What I end up doing is going back to the Events page and then try viewing the recording again and it usually loads up. My Internet download speed is almost 400Mbps and my home Wifi is very fast and stable, with no issue with any other devices.
Out of curiosity, are you clicking on the notification and the video is not loading from there, then you go into the event viewer and the video loads from there?
I ask that particular scenario because it happens to me quite often as well. In general I believe it is because you are getting the notification before the video has completed recording and it’s still taking time to upload to the server, process, and be ready for viewing via the event.
Maybe I wasn’t clear, I am clicking a video that was already recorded on the Events page and not from the notification. I actually turned off notifications because I kept receiving too many of them and nothing was labeled correctly, if at all.