ibn Shu‘bah. For more than three hundred years, no one claimed that it was ‘Alī’s grave, nor did anyone visit it.
Another is “the grave of ‘Abd Allah ibn ‘Umar” in al-Jazīrah. There is agreement that ‘Abd Allah ibn ‘Umar died in Mecca in the year Ibn al-Zubayr was killed. He requested that he be buried outside the Sacred Precinct because he was one of the Emigrants. This proved difficult for them, so they buried him in the upper part of Mecca.
Another is “the grave of Jābir” outside Harrān. There is agreement that Jābir died in the Prophet’s city, Medina, and that he was the last of the Companions to die there. Another is a grave in Syria attributed to “Umm Kulthūm” and “Ruqayyah.” There is agreement that both died in Medina during the Prophet’s lifetime, peace and blessings be upon him, each while married to ‘Uthmān.
This confusion arises simply from people sharing the same names. Perhaps someone bearing the name of one of those mentioned died and was buried in one of these places, and some ignorant people then assumed that the deceased was one of the Companions.