I've tried different browsers but the Challenge for the Custom Objects and Fields is not visible.  (On Trailhead for the Admin Beginner)  Furthermore, the feedback link on this page does not work.  As a result, I cannot complete this module as it remains stuck at 75% even though I've finished everything before and after it.  Please advise so I can get this marked as complete?

The URL in question is:  https://trailhead.salesforce.com/en/trails/force_com_admin_beginner/modules/data_modeling/units/creating_custom_objects_fields
 

I've tried different browsers but the Challenge for the Custom Objects and Fields is not visible.  (On Trailhead for the Admin Beginner)  Furthermore, the feedback link on this page does not work.  As a result, I cannot complete this module as it remains stuck at 75% even though I've finished everything before and after it.  Please advise so I can get this marked as complete?

The URL in question is:  https://trailhead.salesforce.com/en/trails/force_com_admin_beginner/modules/data_modeling/units/creating_custom_objects_fields
 

I've tried three different browsers, as well as logging out and logging back in. There is no challenge at the bottom of Create Custom Objects and Fields in the Data Modeling Trailhead. Clicking the bookmark on the right hand list does not work either. Is this a bug?