Yes, the harness does have a tendency to slip around since my front leg is missing. They have come to realize, however, that this is primarily an aesthetic issue since they can still grab the handle and straighten it out when needed. But they are still always adjusting it!
They do suggest adjusting the front buckles so the neck strap is snug, but not too tight. This does help a bit, as does keeping the chest and belly straps snug, but again, not too tight.
Please join the forum discussion on this topic if you have any words of advice for Louise and Carver! We look forward to hearing from you.