Hi,

I am currently completing the Module 'Create Analytics Apps' and am getting the following error:

Module link: https://trailhead.salesforce.com/modules/wave_apps_basics/units/wave_apps_creating_wave_apps

There was an error executing the Find_Last_Stage_Updates node: Sort dimension/measure not found in Edgemart: Unique_Sort_Key (02K0Y000000Y5MDUA0_03C0Y000000OQ3DUAW)

On 'Check and Schedule the Dataflow' section, part 11. 

Has anyone got any suggestions as to how I can go about getting this fixed?

In this Trailhead challenge : https://trailhead.salesforce.com/en/modules/wave_apps_basics/units/wave_apps_creating_wave_apps 

I am stuck at the step where I have to upload the JSON into the Monitor Data Tasks. While waiting for it to complete .. it fails as in 
this screenshot :


I know in this challenge it is just multiple choice quiz. But in the later Analytics trailhead section, I need to make it succesful in order to complete the step correctly.

Please help