Himachal Road Transport Corporation [HRTC] — lost thermos flask with costly phone lid with cotton bag

I have travelled from new delhi to shimla on 18/6/18 at 8:30 pm by hp 63a 522a in seat no 18-22. I forgot above thing in bus seat no 21when boarded out. Again when i come to realize i found bus was there i knocked the door which was closed inside but driver didn't open the door. They told me you will get in lost and found department. But didn't not get. I am still in shimla what can i do? Pls help me. [protected]