The phrase "over the line" is often used to describe a situation where someone has crossed a boundary or gone too far. There are many different synonyms that can be used to convey a similar idea, depending on the specific context and tone of the situation. Some possible options include "beyond the pale," "unacceptable," "inappropriate," "out of bounds," "against the rules," "too much," and "excessive." Each of these phrases can help to communicate the idea that someone has gone too far in their behavior or actions, and may need to be reined in or corrected in some way.