Step 1. Identify the problem. In this case it was 4 broken threads in the fabric.
Step 2. Mark with thread where the broken threads are so they would be easilly found when required.
Step 3. Carefully remove the stitching. Appologies to the lady that did the stitching but it had to come out so I could get to those broken threads.I had to use my magnifier and good light so I didn't do any more damage. The unpicking left a few holes from the stitching, but these will come out later either just with handling or by easing the threads back in place with a needle.
Mandy had kindly left me some space to work with so I worked a row of satin stitch to give me an anchor point. The row of satin stitch will be decorated at a later date.
At this point I would like to add that this fix is not suitable fo all mistakes. Each error has to be assessed in it's own surroundings to work out which is the best and least noticable way to.
Three cheers to my motto - "Anything is Fixable" . Hip, hip hurrah.