How can a wife be compensated for her dower (mahr) that her husband took in 1965 CE and has not repaid until 2019 CE?

This husband owes his wife this amount, and he must return it without any increase for the delay, unless he voluntarily offers an increase as a gift and an act of generosity, which is permissible, even desirable. Given the significant changes in currency exchange rates, a group of contemporary scholars believes that this should be taken into account when settling deferred debts if there is egregious deception or a currency collapse that causes considerable harm to the creditor.