Legend [WARNING]

I got this warning message while plotting a legend:
legend [WARNING]: not a valid number and may not be decoded properly.

command line:
gmt legend 3.txt -Dg22.50/31+jTL+w4.50c

codes in “3.txt”:
N 2
S C c 0.15i BURLYWOOD -
L - L Very High

Seems you have two C’s (C c) and basically not following the legend input format. Read the docs.