Sayyed Mohammad Al-Musawi, Sayyed Mohammad al-Musawi is originally from Iraq and heads up the World Ahlul Bayt Islamic League in London. Other than being involved in various humanitarian projects, he frequently responds to... Answered 1 year ago

Praying in congregation is highly recommended and the reward of every
Raka’at of it is multiplied by thousands of times. If you are in a
place where congregational prayers are held and your not participating
in it amounts to an insult to the Imam of the Jama’at or the
Mo’meneen, it will then be sinful not to participate in the said
congregational prayers.

There is another case, when the person does not know how to pray
individually or cannot recite the Qira’at properly, then he must join
an available congregational prayer.