Hi Ram,
I see you have logged a ticket on this. I have taken the incident and will help you on this. But for public knowledge of the current status is that on my side the refresh button is working fine so I don't know why it is failing with you and we are going to need to figure that one out.
The refresh button should work, as it has always worked with excel previously. If it is not supposed to work with Excel then it should be disabled for these datasources; that would mean putting in a fix request.
I will respond back to you on your incident and we can continue to work there.
Kind Regards,
Trevor Dubinsky