Is it permissible for a person who vowed to allocate a portion of his money to charity upon the success of his deals to offer his services and deduct the value of these services from the money designated for charity?

Vowing is disfavored (makruh) due to the prohibition of the Prophet, peace and blessings be upon him, who stated that "it does not bring forth good, but only extracts from the miser." This prohibition has been interpreted as disfavor (karahah) because Allah Almighty praised those who fulfill their vows, and the Prophet, peace and blessings be upon him, commanded the fulfillment of vows of obedience. Whoever vows money must disburse it, and it is not permissible for him to substitute it with a service.