Unnecessary legend problem when applying stat_summary

[Jihooevelyn]

Hello,

When I draw this graph, there is an unnecessary legend under each plot label "a". When I try to delete this by deleting "color = variable" in the code, it gives the average value of two plots and not for each which is something I need while analyzing the data.

library(data.table)
library(ggplot2)
library(ggpubr)

dt <- as.data.table(mtcars)

dt_selected <- dt[, .(gear, disp, cyl)]

dt_melted <- melt(dt_selected, id.vars = "gear")

p <- ggline(data = dt_melted, x = "gear", y = "value", color = "variable",
            add = "mean_sd") +
  stat_summary(fun = mean, geom = "text", aes(color = variable, label = round(..y.., 2)))

print(p)

Please Help!
Appreciate your help, thank you.