Error when accessing Relevance module in Advanced eDiscovery

Hi All

I was wondering if anyone has seen the below error when trying to access the relevance module in advanced eDiscovery?

Its been working fine up untill today.  I have tried in Chrome, The new Edge and IE and its the same in each.  I have also tried with 2 different accounts that each have full access to the case.

Does anyone have any ideas?

Many thanks in advance for any help.