Sales Invoice generate sales invoices thru php api

Hi

i am trying to generate Sales Invoice but getting error like bellow. how fix it ?

error : ‘File “/home/frappe/benches/bench-2018-07-19/apps/frappe/frappe/init.py”, line 282, in _raise_exception
raise raise_exception(encode(msg))
ValidationError: Due Date is mandatory’

my post data is :
{“data”:{“taxes_and_charges”:“POS Taxes”,“items”:[{“cost_center”:“Paintball - D9",“qty”:“1”,“owner”:"dhaval@d9adventures.com”,“item_code”:“2002 Beginner Paintball Package”,“parenttype”:“Sales Invoice”,“parentfield”:“items”}],“taxes”:[{“charge_type”:“On Net Total”,“description”:“CGST”,“parenttype”:“Sales Invoice”,“account_head”:“CGST - D9”,“parentfield”:“taxes”,“included_in_print_rate”:1,“rate”:“9”},{“charge_type”:“On Net Total”,“description”:“SGST”,“parenttype”:“Sales Invoice”,“account_head”:“SGST - D9”,“parentfield”:“taxes”,“included_in_print_rate”:1,“rate”:“9”}],“cash_bank_account”:“Cash - D9”,“is_pos”:1,“submit_on_creation”:1,“against_income_account”:“Service - D9,Sales - D9",“party_account_currency”:“INR”,“owner”:"dhaval@d9adventures.com”,“price_list_currency”:“INR”,“payments”:[{“mode_of_payment”:“Cash”,“amount”:480},{“mode_of_payment”:“Card”,“amount”:0}],“customer_name”:“Retail Customer - From App”,“update_stock”:1,“company”:“Delta 9 Sports Management LLP”,“customer”:“Retail Customer - From App”,“territory”:“Vadodara”,“is_opening”:“No”,“customer_group”:“Daily Players”,“naming_series”:“R.#####”,“currency”:“INR”,“debit_to”:“Debtors - D9”,“remarks”:“POS - 102000631 - Kaveesha”,“posting_time”:“18:24:20.000000”,“posting_date”:“2018-07-25 18:24:20”,“set_posting_time”:1,“selling_price_list”:“Basic Member”,“discount_amount”:0,“apply_discount_on”:“Grand Total”,“company_address”:“Delta 9 Adventures-Billing”}}

thanks’ in advance );

Looks like are not supplying a mandatory field.