Stop using, contact Dior, seek legal advice, etc.
1. Stop using: Stop using Dior’s CD trademark immediately to avoid further infringement.
2. Contact Dior: Contact Dior or its agents, explain your situation to them, and request permission.
3. Seek legal advice: If you cannot contact Dior or its agents, or you have used the trademark for a long time, you should consult an intellectual property lawyer to understand your rights and responsibilities. Explore solutions.