[Mrhind]

This happens because depth in the underworld is very low. (your model)
It happened to me once I tried to make a parking near the train tracks (underground), on one side of the parking lot, the character or vehicle, disappeared, I guess that's why, since the depth of the underground underworld has a "limit" "of visualization so to speak.

Although, I'm not totally sure, since this doesn't happen everywhere, u should try.

Example: (is a normal map created with objects of sa-mp)

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