Make sure your fabric is prewashed. Your steam a seam will stick better if the fabric has been washed. Sometimes you can iron over the fabric to warm it up a little before placing your steam a seam on it and it helps to stick to the fabric. If your steam a seam is just dried out, I don't really know what to do about that, but how about placing it in a plastic bag and putting it into the fridge or freezer for a little while? I have no idea if the humidity will bring the sticky back, but I have heard of people doing this for quilting thread, (I think it was thread!
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