Fermented Spider Eye texture doesn't work with resource-packs

I wanted to make a resource-pack work with the "Fermented Spider Eye" texture to look like what I wanted to make for a data-pack: "Heart - 1.16.2", but, the "Fermented Spider Eye" texture doesn't work to replace the vanilla texture. I checked, but it didn't have any problem with it. The description is the same for the data-pack description. I don't know what I am doing wrong here, but there might be something I'm doing wrong that is causing this problem. Please check the resource-pack code, please.