Story Map Tour Saving Error

[NusratFatema1]

Hi,

 I am using Story Map tour template for one my project. I have used a published  feature class which has all the locations , PIC URL , Thumbnail URL ,  with  additional fields  that represents info for  each locations. 

The picture URl seems to works fine and I was able to save my story map after making few changes. But The Thumbnail URL( which  I kept it the same as the Pic URL) is not working correctly. When I  added the Thumb URL  link  and tried save it gave me the following error

Would appreciate your help.

Thank you 

Nusrat