I don't understand your question. Are you saying you violated the masquerade, then paid Silvia to remove it, she did, and the hunter in the alley is still there? That's intended. Hunters who come to town won't give up the hunt, even over time. They are tenacious and will continue to look for you even after it appears you've gone. You will need to dispatch her in your own way. Make the hunter become the hunted.