i lost my necklace wtf

so for context i go to a private catholic school which is the WORST being literally the only alt kid ever. But anyways i have this necklace i got from one of my very best friends that moved away and i lost it. The other one she gave me broke THE VERY SAME DAY! it makes no sense since its a heavy duty chain too and just BAM its gone. I lost the skeleton heart one she gave me, i lost it in the hallway and i remember specifically where but its not there. So reasonably, i think somebody took it and took it to the lost and found. Nope, not there either. So now im scavenging that hallway like its the last of my days because theres no way in hell i'm ever getting that back from her specifically and just UGHHHASDFDSF i hate this school >:(

I'm 1000% sure somebody took it and just stole it, i've been wearing it ever since she gave it to me which was by the way, the start of last year. So for two whole years i've been wearing it and everybody knows, and i mean EVERYBODY. So if somebody else is wearing im so confronting them because what the hell man. Like I know i lost it but its still mine, isn't it? Jada literally bought that for me as a gift :(