"Zainab used to be called "Barrah" (good), and it was said that she was praising herself. So the Messenger of Allah ﷺ changed her name to Zainab."
أَنَّ زَيْنَبَ كَانَ اسْمُهَا بَرَّةَ فَقِيلَ لَهَا تُزَكِّي نَفْسَهَا فَسَمَّاهَا رَسُولُ اللَّهِ ﷺ زَيْنَبَ