What is the validity of a slave's payment towards manumission if the master apostatized after the contract but before full payment?

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If the slave makes payments toward manumission while the master is an apostate, the manumission remains suspended (mawquf). If the master embraces Islam, the payment is confirmed as valid, establishing the slave's freedom. If the master dies or is killed while in apostasy, the payment is void, and the slave remains enslaved.