RigidbodyConstraints.FreezePositionY on button press

Hey guys im trying to make a script that lets me essentially float at when i hold a button down, and when i release it i want to stop floating. my character floats and moves perfectly when i freeze position y in the rigidbody constraints, so i was trying to set up a code that froze y when i press a button and unfreeze when i let go. this is what i whipped up but i didn't work. #pragma strict

 var originalConstraints : RigidbodyConstraints;
  
 function Awake(){
      originalConstraints = rigidbody.constraints;
 }
 { 
 if (Input.GetKeyDown("E"));
 {
      rigidbody.constraints = RigidbodyConstraints.FreezePositionY;
 }
 else
 {
      rigidbody.constraints = originalConstraints;
 }
 }

i'm fairly new to unity but im learning fast. i think theres just a few things i dont quite grasp. i also would like to somehow store the ability to float in like a true/false thing. so i can make it an item pickup. thanks so much for your help future helpers.