The ignition switch/cylinder is worn out.
Hello. This is a common problem with 2003 Honda vehicles. The wafers in the ignition switch/cylinder are getting stuck in the cylinder, which is causing it to not turn when the key is in it. The ignition switch cylinder will need to be replaced. The new ignition switch/cylinder and key will also need to be programmed, so it will work properly to start the car. This usually needs to be done by the dealer, locksmith, or a shop that has the ability to reprogram keys to your car. Have a certified technician, such as one from YourMechanic, inspect your ignition switch cylinder, to see if replacement will be necessary.