Offering supererogatory Prayer after Iqamah for obligatory Prayer is announced
If while offering a supererogatory Salah, the Iqamah for the obligatory Salah is announced, should I stop praying the supererogatory Salah in order to join the obligatory Salah?
If the Iqamah for the obligatory Salah is announced, you have to stop the supererogatory Salah so that you can catch Takbirat-ul-Ihram (saying: "Allahu Akbar [Allah is the Greatest]" upon starting Prayer) with the Imam. This is based on the authentic Hadith in which the Prophet (peace be upon him) said,
When the prayer commences then there is no prayer (valid), but the obligatory prayer.
May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.