Same here.
I’m the owner of the project/chat, and I’m seeing the same behavior: “Chat is Private. Ask the owner to update this chat’s sharing permissions.” In my case, the project and deployment are still live, but the chat access is broken, and I can also hit “Failed to submit message” in new or existing chats.
One useful data point: the same account can still access v0 from my phone, but my PC consistently fails. That makes this look less like a deleted project and more like a chat/session/workspace permissions bug.
Happy to provide timestamps, screenshots, workspace info, and affected chat URLs if that helps engineering narrow it down.