1. Well,the andlord does not have any legal right to claim money to change the name of the landlord.
2. on death of your father his legal heirs acquires right of tenancy by law of succession. So even if he does not change name as long as he receives rent form you your right is protected.
3. Next time send rent to his bank account.
4. You can though negotiate with him to lessen the amount so you cna resolve the problem amicably.