Hi Mary. There is an old saying in woodworking: "I cut it three times, and it's still to short". Meaning once you have cut it to small, you can't fix it. A spiral blade leaves too wide of a kurf.
For any puzzle, weather it's a zig saw puzzle or a stand up puzzle, you must use a flat blade. It makes a much thinner kurf. For jigsaw puzzles, you want to use a 2/0 or smaller blade. Flying Dutchman sells a puzzle blade that is a 3/0 skip tooth blade.
My advice is to recut the puzzle with a more appropriate blade.