KRob ... you may be wondering about all our comments to test it out before you leave the repair shop.
You see ... it may be doing everything right for them.
And if you do it in front of them, you know it is working .... or if it something you are doing, then they can help you trouble shoot.
Add to the fact, be sure to tell them all the variables of when problems are happening. The best is to take a sample of the work. That way they can duplicate it in their testing as they repair ... and again, when you test drive before leaving for home, duplicate the fabrics/battings/thread, etc. that the problem was with.