Traffic Vehicles Dont Spawn at Random Plz Help.

So i have this weird issue with the beam traffic where when i load a map it only spawn certain cars. It'll spawn like a d-series, a bastion, and a t-series and spawn nothing but those for the entire time i play that map. The car selection changes when i change to a different map but it still only spawn a few select cars. It didn't used to be like this it just randomly started. It used to spawn all types of cars but not anymore. Im not sure what to do so i've come here for help. Thanks.