My crown is broken off from the gum lines. What do I do? (Photo)

I hav had 1 crown( front tooth) over 15 years. It was still look good. Last year I decided to have my 10 teeth veneers, so the dentist replaced the old crown to the new one together with other 9 porcelain veneers. The fixed of the front veneers didn't look right so he had to remove the new set of 6 front teeth( including the crown) to put another new set on. You can amazing what my real teeth and been suffering. 6 months later as it yesterday, my crown has broken off right on the gum lines.