It is not permissible for a Muslim to
forsake a fellow Muslim, unless he commits a prohibited act that he is advised to give up but (Part No. 26; Page No. 107) he persists This is provided that there is a considerable benefit in boycotting him, such as deterring him from his action. This ruling is based on the general indication of the statement of the Prophet (peace be upon him) that reads:
All people amongst my Ummah (i.e. Muslims) will be forgiven except for Al-Mujahirun (people committing sins and not being ashamed to announce it in public)
May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.