question #1 Sahih Muslim Introduction 81, Introduction, Narration 80 : What are the potential issues that can arise from using nicknames instead of birth names in hadith narration?

‘What an excellent man is Baqiyyah, if it were not for the fact that he would provide a nickname for [those who were better-known by] the birth name, and he would provide the birth name for [those who were better-known by] a nickname. For a long time he would narrated to us on authority of Abī Sa’īd al-Wuhāthī, then when we investigated [we were surprised that] he was Abd ul-Quddūs ’.