Missed witr prayer

Wa’alaykum as Salam wa rahmatullahi wa barakatuhu,

Witr is compulsory (Wajib). Hence, you should endevour to pray it before dawn. It is a sin to delay it until after its prescribed time.

However, if you missed it, together with repenting, you my pray it in the morning, before or after sunrise.

And Allah subhanahu wa ta’ala knows best.