Plant chage error

Internal error: You passed an empty string for 'flow_data[subscription_update_confirm][items][0][price]'. We assume empty values are an attempt to unset a parameter; however 'flow_data[subscription_update_confirm][items][0][price]' cannot be unset. You should remove 'flow_data[subscription_update_confirm][items][0][price]' from your request or supply a non-empty value.