Get a plain-language read on what you're dealing with, a documentation system that holds up, and a step-by-step path for HR or external escalation if it comes to that.
That makes it hard to know what matters most, what to write down, and what to say if reporting becomes necessary.
Without dates, specifics, witnesses, messages and impact, the issue is easier to minimize than it should be.
The answer is neither panic nor silence: it's a calm sequence of fact-building, documentation and the right escalation path.
Once the issue is categorized and documented properly, the next move becomes much easier to make.