If there is no water, one tayammum is sufficient as long as he didn’t break his wudhu.

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If you made ghusul that resulted from sexual intercourse, ejaculation or from being pure from menses or postnatal bleeding, then this is sufficient and you don’t need to perform a separate wudhu. Kindly refer to the following link(s): https://www.youtube.com/watch?v=fm4Ru0IFoHQ

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This seems fine as the Prophet salla Allahu alaihi wa sallam used to perform wudhu without taking off his ring.

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