How to add custom field within EDD activation output in wordpress

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C#

PHP

WordPress

hi,
I use Easy Digital Download (+ Software Licence ) & Wordpress to sell my products online.

Software Licence is a plugin that generates a product license when the customer buys my product and activate it by API.

the JSON Output :

{"success":true,"license":"valid","item_name":"Custom Template #2","license_limit":9,"site_count":1,"expires":"lifetime","activations_left":8,"checksum":"66c43d9bba464dc78ff26c927","payment_id":"1297","customer_name":"customer naame","customer_email":"mail@yahoo.com","price_id":"2"}

I create a custom field which the customer will write it's company name in it ( id = companyname), I need this field value appear in the JSON Output

{"success":true,"license":"valid","item_name":"Custom Template #2","license_limit":9,"site_count":1,"expires":"lifetime","activations_left":8,"checksum":"66c43d9bba464dc7849fd6c927","payment_id":"1297","customer_name":"customer name","customer_email":"mail@yahoo.com","price_id":"2" ,"companyname":"customer company name"}

What I have tried:

i tried to develop software license code but i faild