Leopard gecko Mochi - orange/white speckled, small

Lost leopard gecko Mochi: orange and white speckled, about 4 inches long, with a faint brown stripe down the back and a slightly chipped tip on the tail. I had him in a small black travel terrarium with a red heat mat. Yesterday around 6:20pm, he vanished from our flat near the Baltic Market on Parliament Street in Liverpool. He's shy but gentle, and loves warm spots behind rocks in the tank; he's not easy to spot in the dark. My daughter adores him and he's been part of our family for over a year; we're really worried and just want him back safe.