You can't fix the new GIF as the problem is now in thew layers as you can see from the thumbnail.
Your layers should have just one frame per layer, so what might work is deleting all but the first frame in the Timeline. Then use Make frames from layers. The bottom line here is that GIF will export just how it plays in the timeline, so you can see if it is right before exporting.
If this does not work, can you show us a screen shot of your entire workspace with timeline and layers panel visible.