Just guessing here, Edward, but this is probably related to the new field and feels like a regulatory thing for brokers and advisors. So I guess unless you are a broker or advisor, pass the empty string.

闯ü谤驳别苍

From:

Limit Order With Manual Order Time

The Limit Order With Manual Order Time is a with ManualOrderTime property.

Order order = OrderSamples.LimitOrder(action, quantity, limitPrice);

Placing a Limit Order With Manual Order Time
The Manual Order Time field is required for, and becomes editable for, "manual" orders, which are orders that originate from a client (whether by phone, email, chat, verbally from the floor, from another desk, etc.) and are then entered into the system. The Manual Order Time field is not used for client orders received electronically, nor for orders that originate from the account manager (with discretion) in the client's accounts, or when an order is allocated to ALL accounts or among multiple accounts using an account group or model portfolio.

client.placeOrder(nextOrderId++, ContractSamples.USStockAtSmart(), OrderSamples.LimitOrderWithManualOrderTime("BUY", Util.StringToDecimal("100"), 111.11, "20220314 13:00:00"));

Canceling a Limit Order With Manual Order Time
The Manual Order Cancel Time field is required for, and becomes editable for, "manual" order cancelations, which are order cancelations that originate from a client (whether by phone, email, chat, verbally from the floor, from another desk, etc.) and are then entered into the system. The Manual Order Cancel Time field is not used for client orders cancelations received electronically, nor for orders that originate from the account manager (with discretion) in the client's accounts, or when an order is allocated to ALL accounts or among multiple accounts using an account group or model portfolio.

client.cancelOrder(nextOrderId - 1, "20220314 19:00:00");