Props aren't visible and I get an error each time I spawn something

For some reason my server has recently been having issues where all props, entities and vehicles are just not even visible.

Also, each time I attempt to spawn something it shows this error in the server console:

SetPos( -1.#IND00 -1.#IND00 -1.#IND00 ): Ignoring unreasonable position.

Please help!