Lightning Experience Rollout Specialist STEP 7

Hello...

I am trying to resolve this error without success...would you help me...


1 - I selected "All Time"
2 - I am showing Opportunity Names by each stage.
3 - As you can see I added the funnel chart.
4 - I do not know what that point means...

This is my report...

Looks like Challenge 7 is not working for me.. I tried with 2 separated Playgrounds from the scratch and it still fails with weird error, even though I think I've done everything right. I have no idea what else I should try.

Error message:
There was an unhandled exception. Please reference ID: GFXKWRGA. Error: Faraday::ClientError. Message: BAD_REQUEST: Specify a valid value for the source parameter.