If sniffing water into the nose is obligatory, must one who performed ablution while his nose was blocked and it later became unblocked repeat his ablution or his prayer?

A blocked nose does not prevent the obligatory sniffing of water into the nose (istanshaq), and it is sufficient to get the water to the lowest permissible level. Whoever is completely unable to perform istanshaq should wash the healthy parts and perform tayammum for the part they are unable to wash. If the member recovers, their tayammum and ablution become invalid, but they do not need to repeat the prayer. Tayammum becomes invalid when the excuse that permits it ceases to exist or when the prayer time expires. However, ghusl for janabah does not become invalid when the prayer time expires.