I forgot to offer the `Asr (Afternoon) Prayer and then remembered an hour and a half later. It was the time when offering Salah (Prayer) is Makruh (disliked), so I delayed it and I offered it with Maghrib (Sunset) Prayer.
What is the ruling on this?
If the case is as you mention, you have committed a mistake when you delayed the `Asr Prayer until sunset. You should repent and seek forgiveness from Allah. If you forget an obligatory Salah, or if you are asleep at its due time, you should offer it when you remember or awaken, as the Prophet (peace be upon him) stated,
If a person misses a Salah because they were asleep or out of forgetfulness, they should offer it when they remember it; there is no Kaffarah (expiation) for it except this.
(Part No. 6; Page No. 25) May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.