Hazrat Shaikh Moulana Muhammad Zakariyya (rahmatullahi ‘alaih) once mentioned:
Due to being engaged in collective Deeni Aa’maal, if one was unable to fulfil some nafl act (e.g. performing tahajjud), then there is no problem in this as this is also an important aspect of Deen and carried out for the sake of Allah Ta’ala. (Qutbul Aqtaab Hazrat Sheikhul Hadith Moulana Muhammad Zakariyya (rahmatullahi ‘alaih) pg. 400)