CURL Request in PHP to Post To API

Use this CURL request in PHP to place an order into the system. [login to view URL] I've done some work, it may help and may be close to working ... The following works on our server and with the Sendle API: [login to view URL] However it returns the following error. I believe it has something to do with the format of the data in CURLOPT_POSTFIELDS. Array ( [messages] => Array ( [description] => Array ( [0] => can't be blank ) [sender] => Array ( [0] => Array ( [contact] => Array ( [0] => Array ( [name] => Array ( [0] => can't be blank ) ) ) [address] => Array ( [0] => Array ( [suburb] => Array ( [0] => can't be blank ) [postcode] => Array ( [0] => can't be blank ) [state_code] => Array ( [0] => can't be blank ) [address_line1] => Array ( [0] => can't be blank ) [state_name] => Array ( [0] => can't be blank ) ) ) ) ) [receiver] => Array ( [0] => Array ( [contact] => Array ( [0] => Array ( [name] => Array ( [0] => can't be blank ) [email] => Array ( [0] => Either email or Sendle ID must be present ) ) ) [address] => Array ( [0] => Array ( [suburb] => Array ( [0] => can't be blank ) [postcode] => Array ( [0] => can't be blank ) [state_code] => Array ( [0] => can't be blank ) [address_line1] => Array ( [0] => can't be blank ) [state_name] => Array ( [0] => can't be blank ) ) ) [instructions] => Array ( [0] => can't be blank ) ) ) ) [error] => unprocessable_entity [error_description] => The data you supplied is invalid. Error messages are in the messages section. Please fix those fields and try again. ) Also, we'll be supplying the information to this page the URL. So can those variables be used in the curl request to Sendle? i.e. I.e. [login to view URL] Luthor&receiver_address_line1=80 Wentworth Park Road Once the order is placed in Sendle, redirect to another page. If there is an error, return the error. I can provide login details to the Sendle backend to check your order requests if need be. Thanks!