There was an unhandled exception. Please reference ID: WDCZKMBV. Error: Faraday::ClientError. Message: INVALID_FIELD: and lastname = 'franklin' and astro_location__latitude__s = 37.553837 ^ ERROR at Row:1:Column:80 No such column 'astro_location__latitude__s' on entity 'Contact'. If you are attempting to use a custom field, be sure to append the '__c' after the custom field name. Please reference your WSDL or the describe call for the appropriate names.

I created the custom field on the contact standard object and displayed it as decimal but got this error message. My org does have namespace created as I have been using this org for sometime as I have have been collecting badges and I don't want to create a new org because then I will not lose my badge count. I did pass the first challenge to create the contacts but the field name does not seem to work.
 

I am using a Mydomain enabled dev org on gs0 (Winter 16) and going throught the exercise in Trailhead. 

Follwed every step and when i click on Preview it takes me to my app (looks right) - https://skypeforbiz-dev-ed.lightning.force.com/c/Sfb.app

But it errors out with -

Lightning components require My Domain. Please contact your system administrator for more information.

Any idea what I might be missing? My org is defenitely provisioned with MyDomin.