The blacklist of appointment registration refers to the act of being blacklisted by the Children's Hospital affiliated to Chongqing Medical University due to some illegal operations or malicious acts, which restricts appointment registration. To delete the reservation registration blacklist, you can try the following methods:

1. Contact the hospital: You can directly call the Children's Hospital affiliated to Chongqing Medical University to consult the specific process of lifting the blacklist. They may ask you to provide relevant identification, explain the reasons for the violation and other materials, and verify them according to the situation.

2. Abide by the regulations: After deleting the blacklist, it is recommended that you strictly abide by the hospital's appointment registration regulations to avoid violating the relevant regulations again and being blacklisted again.

3. Reasonable use: When making an appointment, please ensure that you provide real personal information and medical needs, abide by the appointment registration rules, and do not make false appointments or other illegal operations.

It should be noted that due to different policies of hospitals, the specific procedures and regulations for lifting the blacklist may be different. You still need to contact the Children's Hospital affiliated to Chongqing Medical University directly to get an accurate solution. If you have a specific personal situation, it is recommended to communicate and negotiate according to your actual situation.