For world textures to load correctly, you need to have enough VRAM to spare and have FiveM on a fast drive. If the problem persists, you can try raising the Extended Texture Budget value on Pause Menu's settings.
Pause Menu > Settings > Graphics > Extended Texture Budget
Pause Menu > Settings > Graphics > Extended Texture Budget
Pause Menu > Settings > Graphics > Extended Texture Budget
Pause Menu > Settings > Graphics > Extended Texture Budget
