Salaam.
If you miss a prayer because you don't bother to do it. Is the activity you are doing at present (even if it is halaal e.g. Spending time with family) be haram? Or would the missing of the prayer be an independent sin?
It was narrated that ‘Ubadah bin Samit said:“I heard the Messenger of Allah (ﷺ) say: ‘Five prayers that Allah has enjoined upon His slaves, so whoever does them, and does not omit anything out of negligence, on the Day of Resurrection Allah will make a covenant with him that He will admit him to Paradise. But whoever does them but omits something from them out of negligence, will not have such a covenant with Allah; if He wills He will punish him, and if He wills, He will forgive him.’” (Sunan Ibn Majah)
On the authority of Abu Hurayrah (may Allah be pleased with him) from the Prophet (ﷺ), who said:Allah (mighty and sublime be He) says: The first of his actions for which a servant of Allah will be held accountable on the Day of Resurrection will be his prayers. If they are in order, then he will have prospered and succeeded: and if they are wanting, then he will have failed and lost. If there is something defective in his obligatory prayers, the Lord (glorified and exalted be He) will say: See if My servant has any supererogatory prayers with which may be completed that which was defective in his obligatory prayers. Then the rest of his actions will be judged in like fashion. (Jami' at-Tirmidhi, Sunan Abu Dawud, an-Nasa'i, Ibn Majah and Ahmad)
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Salah is very important. the first pillar of Islam. Don't abandon salah intentionally. If you miss salah unintentionally, you can offer it as soon as you remember
Abu Qatadah narrated:"They asked the Prophet about when they sIept past the Salat. He said: 'There is no negligence in sleep, negligence is only while one is awake. So when one of you forgets a Salat, or sleeps through it, then let him pray it when he remembers it.'" (Jami` at-Tirmidhi )