Paystack form error on clicking pay wp-admin/admin-ajax.php

Question

please I need an assistance with how I can solve the paystack form error I am getting recently. The form is not submitting, rather, its giving error on clicking pay button.

{"result":"success","code":"16452315_FV31H029","plan":"none","quantity":1,"email":"[email protected]","name":"","total":75000,"currency":"NGN","custom_fields":[{"display_name":"Pf-currency","variable_name":"pf-currency","type":"text","value":"NGN"},{"display_name":"Full Name","variable_name":"Full_Name","type":"text","value":""},{"display_name":"Payment Option","variable_name":"Payment Option","type":"text","value":""},{"display_name":"Home Address","variable_name":"Home_Address","type":"text","value":""},{"display_name":"Occupation","variable_name":"Occupation","type":"text","value":""},{"display_name":"Office Address","variable_name":"Office_Address","type":"text","value":""},{"display_name":"Phone Number","variable_name":"Phone_Number","type":"text","value":"sc"},{"display_name":"Date Of Birth","variable_name":"Date_of_Birth","type":"text","value":""},{"display_name":"Account Number","variable_name":"Account_Number","type":"text","value":""},{"display_name":"Account Name","variable_name":"Account_Name","type":"text","value":""},{"display_name":"Bank Name","variable_name":"Bank_Name","type":"text","value":""},{"display_name":"Name","variable_name":"Name","type":"text","value":""},{"display_name":"Contact Address","variable_name":"Contact_Address","type":"text","value":""},{"display_name":"Email Address","variable_name":"Email_Address","type":"text","value":""},{"display_name":"Relationship With Customer","variable_name":"Relationship_with_Customer","type":"text","value":""},{"display_name":"Unit Price","variable_name":"Unit_Price","type":"text","value":"NGN750"}],"subaccount":null,"txnbearer":null,"transaction_charge":null}

error getting from admin-ajax.php