I work in a central European country and had a similar issue (see my comment above) where I was the culprit. HR told me they we're approached by my colleague and I should avoid her und stick to the code of conduct. I think my job was not on the line, which prevented me from the moronic defense mode that OP engaged into.

European companies have a duty of care to protect their employees from harm. This harm could be harassment or bullying from other employees. So most companies will have a policy against bullying and harassment. If someone else makes a complaint against you that complaint should be investigated; you'll be spoken to; mediation might be attempted; "guidance" will be given.

If you ignore the guidance they'll start issuing warnings. Those warnings are kept on file to help with potential employment tribunal cases.

In the UK: after two verbal warnings and one written warning you'll be fired. Or sooner, if your behavior meets the gross professional misconduct level. (You punch someone, for example.)