What if the wudhu breaks during salat or during hajj due to a medical condition? Does that salat or hajj not count at all or is there a substitute? What if they cannot keep wudhu for longer than two or three minutes?
If the condition is ongoing and constant such that there is no way the person can complete an act of worship without their wudhu breaking, then their wudhu will suffice and their worship will be valid. If you can keep wudhu for two or three minutes you need to pray directly after wudhu. After prayer, if you break your wudhu you need to perform it again before the second prayer.