How can I sort the Circular heatmap labels in alphabetical order?

The codes where I created the circular in my code are as follows:

library(circlize)
col_fun1 = colorRamp2(c(0, 0.000001, 5, 10), c("#FFFFFF", "#91cf60", "#ffffbf", "#fc8d59"))
circos.clear()

pdf(circle.pdf", width = 15, height = 20)

circos.par(gap.after = c(2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 8))

circos.track(track.index = get.current.track.index(), panel.fun = function(x, y) {
   if(CELL_META$sector.numeric.index == 11) {
     cn = colnames(cpl)
     n = length(cn)
     circos.text(rep(CELL_META$cell.xlim[2], n) + convert_x(1, "mm"),
                 1:n - 0.5, cn,
                 cex = 0.5, adj = c(0, 0.5), facing = "inside")
   }
}, bg.border = NA)

library(ComplexHeatmap)
lgd = Legend(title = "sepal length", col_fun = col_fun1)
grid.draw(lgd)

dev.off()