How to de-activate melee button on xbox controller

hi   ive been a callofduty player for awhile    ive changed camps    ive got only one issue   I keep hitting the melee button in the middle of shooting spree   instead of shooting the guy in front of me   I hit the melee button a little too hard and my police baton or baseball bat is swung  n the guy in front of me kills me without effort coz im twenty feet away from me       he must be saying to himself   why is he swinging his bat 50 feet away from me       Hate it

is it possible to de activate the button     need help here