ifelse setting different argument in ggplot2

I have my dataframe:

test<-data.frame(F1=c(1,2,3,4,5),F2=c(3,4,5,6,7),Group=c("G1","G2","G2","G3","G1"))

I try to set up different point color at different condition:

FF<-function(Ture_or_not){
  p<-ggplot(test,aes(x=F1,y=F2))+
    geom_point(aes(color=Group),size=10)+
    scale_color_manual(values=ifelse(Ture_or_not==TRUE,c("yellow","red","black"),c("black","black","black")))
  p
}

FF(TRUE)

But I got:

Error: Insufficient values in manual scale. 3 needed but only 1 provided.
Run `rlang::last_error()` to see where the error occurred.

May I know what's the problem?