Having issues with the below trailhead module

Create a dashboard named Opportunities Dashboard and save it in any folder
Create a dashboard component using the Opportunities by Type report (use any component you want)
Post a snapshot of your dashboard component to the dashboard Chatter feed

When naming the Dashboard "Opportunities Dashboard" and attemtp to save, Error: This Dashboard Unique Name already exists or has been previously used.
This is not true as there is no such other Dashboard with the same name

Having issues with the below trailhead module

Create a dashboard named Opportunities Dashboard and save it in any folder
Create a dashboard component using the Opportunities by Type report (use any component you want)
Post a snapshot of your dashboard component to the dashboard Chatter feed

When naming the Dashboard "Opportunities Dashboard" and attemtp to save, Error: This Dashboard Unique Name already exists or has been previously used.
This is not true as there is no such other Dashboard with the same name