I guess that something has happened either with their data acquisition scripts (deadlock, infinite loop, I don't know), either they couldn't retrieve data (blocked by the exchanges).
I've seen such situations now and then on various websites showing the market data.
As a nice coincidence, it has started working just minutes before my check. Now it's back to normal, obviously, without the data it couldn't read.


More than 8h without data is indeed a lot.
As others said, another option I also use is https://cryptowat.ch