I hope you are well.
The URL you are trying to access demos is working but it is not totally correct please trying using the URL mentioned on Aspose.Cells for Reporting Services docs
The correct demo URL you tried to access should be
Aspose.Cells for RS Docs
Please feel free to let us know if there is any issue.
Thank you for the answer, but
There are some known issues with SSRS reports when viewed in Chrome and Safari browsers. Our team is working on fixing them. Meanwhile you can access the reports in IE and FireFox.
Please feel free to let us know if there is any further issue.