"Off-quote" message typically indicates that the requested price is not available or cannot be fulfilled at that moment. This can happen for several reasons, such as:

Fast price changes:
In volatile markets, prices move quickly, and the one you want may no longer be valid.

Low market activity:
If there isn't enough buying or selling activity, the price you request may not be available.

Technical issues:
Problems with the trading platform or internet connection can also cause this message.

In essence, an off-quote message means the requested price is unavailable, and the order cannot be executed at that specific moment.