Is expiation obligatory for fulfilling a vow to gift a phone to a specific person if fulfilling it would cause family problems due to the father's objection, especially given that the recipient is well-off?

A lawful vow must be fulfilled, and one is not permitted to deviate from it except in cases of inability, as Allah Almighty says: "And let them fulfill their vows," and the Prophet, peace and blessings be upon him, said: "Whoever vows to obey Allah, let him obey Him." A vow made to a specific person is binding, and that person has the right to demand its fulfillment. One's obligation is discharged if the designated recipient does not accept the vow. One must be gentle with parents to convince them that fulfilling a vow is an obligation and a right due to Allah Almighty, which takes precedence over the right of a servant. If one is unable to fulfill it, its expiation is the expiation for an oath.