The app will put by default new tasks into Inbox but Inbox is not what you see when opening Todoist. Instead you might see that there are no tasks for the next 7 days. There's no logic in it, app's assistant integrated with Google Assistant fails to find any tasks, even if asked specifically about those in Inbox. Todoist is cumbersome and annoying, it's actually a general problem with task apps: they're too much and fail to actually do what they are made for.