Coping pulling away from Concrete

I have an in-ground pool built in the 80's. It has a deck integrated coping (Bullnose Coping) and it is starting to give me some problems. The coping is attached directly to the concrete deck. In a couple of areas, the coping is pulling away from the deck leaving about a 1/4 inch space. What can I do with this space ? Can I put concrete in the gap or some time of adhesive just to prevent it from separating more ? Thank you for you suggestions. Mike