Unfortunately, some default system fonts render these symbols as emoji. You can try to find a font with custom unicode symbols or try https://www.dafont.com/font.php?file=astro_gadget this font and replace the text in the symbol library input box with the symbols you need (i think it would be something like "A B C D E F G H I J K L M N O P Q R S T a b c d e f g h i"
I'll look into possibly creating my own custom font with those symbols properly set :)