What happens to the indenture contract if one party subjugates the other after entering Muslim territory under Aman?

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If one subjugates the other after entering, the indenture contract is nullified. If the slave subjugates the master, the slave gains ownership, thereby nullifying the contract because he is no longer under the master's ownership. If the master forces the slave to agree to the nullification and reverts him to slavery, the contract is void because the land of disbelief (Dar al-Kufr) is a land of subjugation and permissibility; hence, if a free man subjugates another free man, he becomes his owner. However, if subjugation occurs in the land of Islam without prior subjugation, the contract is not voided, and they revert to their previous legal status because the land of Islam is a land of restriction (Dar al-Hatr), where subjugation is only effective with legal right.