They haven't been properly seasoned and greased before use. If they don't slip out, there are three ways to troubleshoot: 1. Bang the molds on a hard surface on each side. The canelés should release Use a thin, heat resistant stick, i.e. a cooking thermometer. Carefully insert around the edges to release. 2. Use a fork and peel it out. If you need to resort to this, take out as much of the canelé as you can salvage (still edible!). Carefully soak the molds in water, being careful not to expose the exterior to water. After soaking for up to 30 minutes, pour the water out and gently wipe away any crumbs with a paper towel.