If we missed Nafil prayer (non-obligatory prayer), can we make it up?

All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.

Yes, it is proved that Umm Salamah said: “The Prophet was busy and did not perform the subsequent two Rak'ahs of Thuhr, so he performed them after 'Asr obligatory Prayer.” [Ahmad in al-Musnad].

Allah knows best.