The FinOps application runs alongside the Access Financials service.
The first thing you could check is the aCloud Status Page for any known incidents.
Just look for Access Financials and if you see a orange triangle, click on it and you'll be given more information about the incident.
IF there are no known incidents on the Status Page, the next things to try would be (in no particular order):
Clearing your browser's cache
Accessing the application from another browser
Access the application from another PC (as a different user)
Access the application from another PC (from outside your companies network)
IF none of the above have resolved your problem: please raise a new case online and reference the title of this article.