This ring has received forces that have moved the head to one side. The customer was unaware there was a problem.
Notice how little metal is over the edge of the diamond. That metal has been worn away just from wearing it.
This is the diamond with a new head attached and diamond set. Notice the amount of metal over the edge of the diamond now.
Look at how straight the head now stands in the ring. This is how it should look. Stop by and have us check your jewelry before you have a loss.