Comment log tagging not working

We are just now upgrading from v9.x and I brought my TST environment to v11.0.1

I was checking all the changes for v10.x and v11.x and the Comment Log Fields' tags are not working.

It appears that when typing the "@" it should start a dropdown with employee names who have access to the record (all our records are "Global" team) and when typing "#" it should allow linking a record. Neither of these seem to work in my instance.

Any suggestions on how to debug? I see no errors in any of my logs or the console.