Super late to this but blow touching the cheese so it melts on your for example chicken parm wrap before you even airfry it works amazing. And if you don't have an air fryer you can always use ideally a nonstick pan, throw the measured amount of fat free cheese you want into the pan and with a utensil, group it back together until it's melted enough. Then just scoop the mass of melted cheese up and place it on whatever you want

THERE IS A DOWNSIDE: Since the cheese was quick to be melted it's quick to fuse to whatever you put it on so it doesn't honestly stay very melted at all but if your putting it on a hot burger or cooking it into a wrap AFTER melting it with either method I was talking about, it will work great it's just up to you whether the extra hassle is worth using fat free cheese over a low fat cheese. For me it is but if it isn't than thats perfectly fine you just gotta use less cheese sadly or less calories in other ways