When I select a class, all text goes away, does someone know how to fix this?

I have just joined the server, when I am in the black box, everything works, but when I select a class, all text disappears. I also get slowness effect but maybe that's part of the tutorial. I see messages pop-up in the chat but the text is not there.

This seems like a really fun server, so does anyone know how I can fix this?
Thanks

 

try doing /class and reselecting your class again

 

are you using any mods?

 

Look at the resource packs you have enabled, I found the some of mine were cause all text to disappear