They say
“I already tried talking to them. Nothing changed.”
Your response
“Then telling you to try again is not enough. Tell me what you said, what they said, and what changed afterward. I’ll decide whether I need to join the conversation or set clearer expectations for both of you.”
First, check this
What did the employee actually try, and did the coworker understand both the concern and the change being requested?
Why this works
The employee may have made a clear, good-faith attempt, or may only have hinted at the problem and assumed it was understood. Asking what happened distinguishes those cases. If direct discussion has genuinely failed, repeating the same advice leaves the employee stuck. The manager can then choose a different step, such as joining the conversation or setting explicit expectations, while still examining each person’s conduct fairly.
Don’t say
“Well, you’ll just have to try talking to them again.”