The website is pretty ancient (and has some GDPR issues that still don’t seem to be resolved) so alot of the parts no longer work, there were places where you could, for example, select invoices I think, but all the invoices are now from 2018/2019 but the dropdown only shows the last 2-3 years as options meaning you cannot select any data.
It would be really nice if it got a refresh / makeover and some of the other components updated so they work again / at all so we can create scenarios on them to challenge developers or use as teaching scenarios.