Sereal Do Nerovision Express-3,1,0,25 Where Is The Sereal Number On My Gun???

Where is the sereal number on my gun??? - sereal do nerovision express-3,1,0,25

I have an LD 24 wild. Kaliber 20-22mag. up / down. Not able to find the number sereal everywhere. not appear to have been deleted from the Internet.