Depending on how long the open seam is and how many I would re stitch it matching the color top thread and bobbin thread with the quilted threads. You can also use a small dab of fabric glue to help if it is just a small area. I used a small bit of fabric glue and hand stitched the seam back together on my first quilt when we found one small 1 inch seam not holding after we got it all quilted and ready for the binding. I was bummed to, but it happens.
Good luck.