Q Code Interactive plugins help

I am using the /strata theme from Q Code interactive and two of the required plugins, the layer slider and the visual composer- have disappeared. I tried reinstalling them and can’t I keep getting an error message saying that the directory can’t be created. The only time I’ve had this problem in the past was when I tried to install a plugin that was already installed but these definitely are not anywhere in my wp files. I do not have the documentation for this theme and haven’t been able to get it from the developers…Just thinking maybe someone here knows what could be wrong.