this happens with honda keys, by the car is 100k driven the keys go flat they stop opening the doors, trunk or end up going in only one specific direction in the ignition.
any famous petrol pump in your area should have key make, get it made from the DUPLICATE key for exact match. make sure you do not let him try carving a 70% done key and then doing the 30% by inserting in your door or trunk lock. tell him to make exactly like duplicate key it will automatically be perfect for all locks.