Cut out the leaking piece
Leaky, crimped-on heater hoses can be replaced with new, expensive assemblies. But you can replace just the leaky section for a fraction of the price. It's simple and cheap to do with a short matching length of hose and a new worm-drive clamp. (You should reuse the factory spring clamp, but you can't reuse the old crimp ring.) Check with a local auto parts store to locate replacement molded hose sections. Or bring in the leaking section and see if the staff can visually match it to a stock hose for another vehicle.
If you can't find the proper molded hose, slide a reshaping coil over a straight section of hose and bend it to the proper angle for your application. The coil will maintain the angle and prevent the hose from collapsing at the bend.