Error: Delivery 4179691 is not eligible for action Ship Confirm.Warning: For Delivery Detail 61735

Hello,

I am getting the below message :

Error: Delivery 4179691 is not eligible for action Ship Confirm.Warning: For Delivery Detail 617351, the following field(s) are not updatable: TRACKING_NUMBER.

I am using the piece of code of the API to ship confirm.

x_return_status := WSH_UTIL_CORE.G_RET_STS_SUCCESS;

               -- Call this procedure to initialize applications parameters

               FND_GLOBAL.APPS_INITIALIZE (user_id        => 1130,

                                           resp_id        => 21623,

                                           resp_appl_id   => 660);

               -- Values for Ship Confirming the delivery

               p_action_code := 'CONFIRM'; -- The action code for ship confirm

               p_delivery_id := c_eligible_orders_rec.delivery_id; -- The delivery that needs to be confirmed