It happens when you lose the connection to the relays.
What app do you use for Nostr? See if you have any updates to make.
Discussion
I've updated #Amethyst and I have paid relays. I uninstall and reinstalled. I don't know how I lost connection. I added my paid relays again. But I can't see anyone. I went to this note to respond to you. My notifications are empty. Thank you my friend. Really!!🫂💜🎨 😔