Last week I was unable to get my key into the ignition to start the mower. I rarely take the key out unless mower is sitting outside the trailer. Other than that key stays in ignition, with NO other keys or even a key ring attached. Now...the key will not go all the way into the slot. I'm having to use a small screwdriver to start and turn off. Is this warranty? I'd like to be able to swap it myself instead of taking mower 25 miles one way to dealer. I'd appreciate any help.