Custom Icons - only 1 showing up from the list in the JSON file

I have created a JSON file for some custom icons (10 of them) I would like to add into my Power BI custom icon formatting options.

The code is all valid as have checked it through codebeautify. I import the file in and it works, however, when I go to the icon section only 1 x icon (forestry) has been added from my JSON file and it is the last one on the list. The others haven't been added and there isn't a scoll option.

 Even though the code is correct have I missed something? The code example is below (have removed the base64code as too long).

Why is it just taking the last icon and not the others? Thank you for any help you can offer. 

{
"name":"Sector Icons"
,"icons":
{
"GraphIcon":{"description":"Alternative Protein","url":
"BASE64CODE"}, 

"GraphIcon":{"description":"Dairy","url":
"BASE64CODE"}, 
"GraphIcon":{"description":"Forestry","url":
"BASE64CODE"} 
}
}