Taraweeh prayer was initiated by the Prophet when he performed it along
with his Companions for three nights. But in the forth night, he did not perform it for fear of it being imposed on the Muslims as an obligatory prayer.
So, it is OK to perform Taraweeh prayer in group sometime and alone some days.
The Companions resumed performing it individually during the lifetime of the Prophet and after his death, until Umar ibn al-Khattab made them perform it in congregation as they used to perform it with the Prophet .
Caliph Umar bin al-Khattab said with respect to Taraweeh prayer - “What a good Bid’ah is this.”
This is not considered as Bid’ah in the deen, as it was done during Prophet time too.
