People used to call it Yathrib and Madinah, but the Prophet ﷺ said, "Allah has named it Taybah."
حدثنا عبد الله حدثنا شيبان بن أبي شيبة حدثنا حماد يعني ابن سلمة حدثنا سماك بن حرب
كانوا يقولون يثرب والمدينة فقال النبي ﷺ إن الله تبارك وتعالى سماها طيبة
Its isnad is sahih. Shayban bin Abu Shayba, Faruq, his hadith is deemed reliable by Muslim, and the imams have accepted his hadith. The hadith has already appeared at 20714, and here it is one of the additional narrations.