If you are referring to 3 rak’ah witr, it is not permissible to sit in the 1st tashahud as in Maghrib.

Type of sitting for 1st tashahhud and the last in witr ?

Prayer | March 26, 2014 10:59 am
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In fardh prayers is it needed to recite bismi before fatiha and before reciting surah ? .throughout the prayer ?
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What to do when one forgets to read surah after fatiha in witr prayer ?