Imperfect infrastructure and staff errors. Judging from the information of the ambulance, the reason why the seal of the ambulance was not signed by two people was due to the imperfect infrastructure and the work mistakes of the staff. Storage and sealing: Before sealing, two nurses will count the drugs and articles according to the base number, and the two nurses will start sealing after checking them correctly. Stamping requires two signatures, and fill in the stamping time.