Cannot find my nerite snail

It's been five days since i last saw my little guy and im getting worried. I know nerites like to hide but he's just been gone. No ammonia spike in the tank and no smell in or around the tank to indicate he's dead. I've checked a bit of my substrate but stratum reallllly doesn't like to be disturbed. I put a nano banquet block in there, but I've never used them before so I can't tell if he ate some or if in 12 hours it's starting to dissolve.

I would remove the block before it pollutes the water.

Nerites are experts at hiding. I have even resorted to removing every piece of decor and thoroughly examining it when I wanted to treat the tank for ich (before I knew it could be treated by heat ). I could not find one of them so I went ahead and treated the tank only to find the snail 2 days later crawling on the substrate.
If it was dead, you'd find it lying on the bottom of the tank somewhere.

Nerite snails (and mystery snails, for that matter) are also notorious escape artists...check the surrounding area around the tank....also, check your filter(s), if there's any way for them to climb into a filter, they'll do it...lots of tasty morsels inside established filters....I have found my nerites inside my HOB filters on more than one occasion

I’d look everywhere, including outside the tank. They are great at escaping/hiding.