Unable to see effects in my server

Hello, I have a very strange problem that is for some reason just happening in my server, the error is that I am unable to see all kinds of effects, including effects from addons / plugins that are installed in the server. I thought at first that this was a problem of mine, and that I was the only one that wast seeing the effects at all, but a friend told me the same thing was happening to him. Then I hopped in sandbox and every effect seemed to be work just as it should, so I realized it was either a problem of the server or gamemode, SantosRP (which is the most probable), after that I installed Crap-Head 's fire system to test if it was just gamemode effects or every effect in general, and I (as expected) was unable to see the fire that the addon generates. I searched everywhere for a solution for this issue and yet didn't find it. I would like to know if any of you know what should I do or what is causing this issue.