Why can't users add topics and posts?

Question

Joomla

Hello. There is a site on the latest versions of joomla, k2 and kunen. Having logged in from the frontend, even the superuser cannot add anything. There is simply no corresponding button and such an inscription appears at the bottom of the page

. Secondly, when I go to the account settings, an error pops up. Screenshot

What did I do wrong?