What would you think if your roommate said you had underarm odor in another dormitory? What would you do to her? Do you want to hit her?

If she slanders you and you don't stink, then you despise her and expose her to her face when appropriate.

If she is right, then you should try your best to keep personal hygiene and try not to affect others.

Sometimes, some people can't smell their own peculiar smell. If this is the case, you can ask someone else to confirm it for you.

You should keep a proper distance from her in the future. But in any case, hitting people is wrong.