LG
Mobile lost

I was traveling from newdelhi to amritsar by train. my lg handset has been thief in train between new delhi and ambala station when i reach amritsar and went grp amritsar to log FIR they said go to cyber crime office in amritsar . when i reach there they said you have lost the mobile in train so you have log FIR in grp amritsar and then again went there they say that you have to log FIR in ambala station. like this one month had past. as my phone have anti theif software i know the phone no of person who hold the phone and the address also. now pls tell what to do now. i have the bill of mobile with me