While opening the data migration cockpit : (Exception raised without specific error)

[897654208074]

Hello Expert,

I'm facing this error, while opening the data migration cockpit.

Issue:
I have two clients. When I log in using the URL from Client A, I don't encounter any errors. However, when I log in using the URL from Client B, I get an error.

Request:
Could you help me understand why this error is occurring and what I should check to resolve it?

Thanks,

Ahmed