For graphics related questions it is a very good idea to include some example data in the form of working data step code so we can test your plot.
When macro values are included, if they are at all critical, then you should provide a definition of the macro variables so they will resolve to expected values when testing.
What does your LOG look like? Copy your log text and on the forum open a text box using the </> icon that appears above the message window and paste the text. I suspect there may be error messages related to the LEGENDITEM statement.