You don't because that's not the problem. And that's not how you correct this...

I'm willing to bet that if there is indeed a live round in the chamber then it's possible that what the problem is a round with too much crimp is jammed in the chamber. You're going to have to muscle that slide back.. Put some elbow grease in there and give it a couple very sharp tugs rearward. OR place the muzzle down against a wood table edge (finger off trigger obviously) and press firmly down on the grip.
If the trigger feels mushy, what happened is you may have pulled the trigger when the slide was not fully in battery, releasing the firing pin but since the slide is stuck the trigger did not reset. Just place the muzzle edge down on the end of a table and press down hard. Give it a couple good pushes and I'll bet the slide will go back ejecting that bad round... It's not Freedom munitions, that could happen with any brand. But mostly with reloads with what I've seen.

I have seen these before with somes guys that reload that have a batch of reloads with too much crimp.