not using my image as starting frame

I've been using Firefly successfully generating images for starting frame to then create video from that image, since yesterday all has been good, and this evening it will not use my image set as the starting frame for the video. It looks as if it uploaded it, but when I generate it disappears from the box and generates at random. I have tried many times, I even restarted the computer several times just in case, but firefly will not take the image set as starting frame, it will generate video with out using it obviously generating a different setting altogether. I have lost more than 1000 credits by this, and can't finish my project. Why is this happening??? I want my credits back.