You can't report the loss without receiving the medical insurance passbook.

Legal analysis: the first collection of medical insurance passbook must be in the name of the applicant and collected by the relevant person in charge of the unit. If for some reason, for example, you have applied for social security, but left your job without getting the passbook, you can take the original ID card to the bank to report the loss directly. You can check the relevant information when you go through the formalities in the bank. If the procedures are complete, you can directly report the loss and reissue it. If the original unit fails to complete the formalities for some reason, you can't report the loss directly at the bank, and you need to go to the local social security to solve it.

Legal basis: Article 23 of the Social Insurance Law of People's Republic of China (PRC), employees shall participate in the basic medical insurance for employees, and both employers and employees shall pay the basic medical insurance premium according to the provisions of the state. Individual industrial and commercial households without employees, part-time employees who have not participated in the basic medical insurance for employees and other flexible employees can participate in the basic medical insurance for employees, and individuals pay the basic medical insurance premium in accordance with state regulations.