out of bounds
US /aʊt əv baʊndz/
UK /aʊt əv baʊndz/

1.
beyond the permitted or designated area
:
•
The ball went out of bounds.
•
That area is out of bounds to visitors.
2.
unacceptable or improper behavior
:
•
His comments were completely out of bounds.
•
That kind of language is out of bounds in a professional setting.