Is it permissible to perform the Duha prayer and the Sunnah of Fajr during Duha time before performing the missed Fajr prayer as a make-up?

Delaying a prayer beyond its prescribed time without a valid excuse is impermissible and constitutes a major sin, for Allah Almighty says: {Indeed, prayer has been decreed upon the believers a book [due at] fixed times.} (An-Nisa, 103). If one misses the Fajr prayer and wishes to make it up during Duha time, the Sunnah is to first pray the Sunnah of Fajr, then the obligatory prayer, following the practice of the Prophet (peace be upon him) and his Companions. It is not permissible to combine the Sunnah of Fajr with the Duha prayer with a single intention, because each has a different purpose, and because one's obligation is to make up the missed obligatory prayer. This is also in accordance with the saying of scholars: "One who owes a missed obligatory prayer should not pray supererogatory prayers."