What is the ruling on the prayer of one who missed the Maghrib and Isha prayers while traveling, due to being unable to perform them at their prescribed times, and performed them after arriving home?

If you arrive home and there is still time for the ‘Isha prayer, there is no harm in that, and the prayer must be complete, not shortened. However, if you pray after midnight, you must repent, as it is obligatory to perform the prayer within its prescribed time, even if by gesturing in a train if you fear the time will expire.