I am getting an error message when saving any item of K2.
Apparently it is in the database. Please, could you help me?
Below is the print screen.

same here. as good as their templates are, the only problem i always have with them is their bad customer service

Those errors suggest that it is the smart search - try going into Joomla Smart Search Component (Admin) -> Smart Search -> Purge all items.

That will sort this error.

You may find you need to do similar with tags and weblinks - just delete the existing entries and this error will go.