Who are the Companions who apostatized during the time of the Prophet, peace and blessings be upon him, or after his death, and then returned to Islam?

A Companion is anyone who met the Prophet, peace and blessings be upon him, as a Muslim and died upon Islam. The Companions are divided into two categories:

1. The first category: Those who accompanied the Prophet, peace and blessings be upon him, and learned from him, such as the Muhajirun and the Ansar. It was rare for any of them to apostatize, as the apostasy from faith after its cheerfulness has mingled with the hearts is far-fetched. The only prominent example is that of Abdullah ibn Sa'd ibn Abi Sarh, who apostatized but then returned to Islam, and his Islam became good.

2. The second category: Those who visited the Prophet, peace and blessings be upon him, and embraced Islam but did not stay long or deeply understand the religion, like many of the Bedouins. A small number of them apostatized after the Prophet's death, peace and blessings be upon him, and some of them returned to Islam after Abu Bakr As-Siddiq fought against them. On the Day of Resurrection, the Prophet, peace and blessings be upon him, described them as "usayhabi" (a diminutive form) to indicate their small number. Among them was Al-Ash'ath ibn Qays, who apostatized but then returned to Islam and married Abu Bakr's sister.