Hello. Those servers that are telling you to get points (even if you do have a S1 license) might have a third party application (like Airio), which might restrict the vehicles that you can drive. You would have to race around a lot, gain a lot of "online stats" etc. on Airio servers to gain points, so that you can drive other cars on those servers.
Mind you, this restriction is placed by the owners of the servers (by using Airio) for their on reasons.