ReMask 5 Save As Question

I am fairly new to Topaz. I have used the ReMask only a couple of times. When I went to use it today I noticed that when I go to Save As, I don’t get the Transparency option that I have gotten in the past… I got it on the first image I saved, but nothing after that. I use them to Layer my Art and so they must be saved as as Transparent, Perhaps I am missing something, but not sure what. If anyone can assist I appreciate it. I am a novice at this, and learning as I go. THANK YOU

NEVER MIND I REALIZED WHAT I WAS DOING WRONG. NEEDED TO SAVE IT AS A PNG.