I am trying to create a sales order from API in ZOHO inventory and I keep obtaining 

1. {
       "code": 4,
       "message": "Invalid value passed for JSONString"
   }

I tried many combinations, but the same error appear.

Yes, I can obtain all sales orders  and all items.

For creating a sales order I use:

- the url:

https://inventory.zoho.com/api/v1/salesorders?ignore_auto_number_generation=false?authtoken=xxxxxxxxxxxxxxxx&organization_id=yyyyyyyyyyyyy

- the JSON:

1. {
       "customer_id": 235260000000310001,
       "salesorder_number": "SO-00009",
       "custom_fields": [
           {}
       ],
       "reference_number": "0905219",
       "line_items": [
            {
               "item_id": 235260000000476073,
               "quantity_invoiced": 2,
               "sub_total": 444,
               "tax_total": 29,
               "total": 550
            }
        ]
   }

Does anyone have any idea about what am I doing wrong?  Or am I missing something ?

Thank you for your help.

Best Regards,

Mihaela