apps.wsh_deliveries_pub.delivery_action is not able to trigger label prints

I have setup a shipping type WMS label which needs to be triggered and printed after ship confirm.

Assign Label to Business flow at Ship confirm business flow also been setup at both user and responsibility level.

Label format rule setup as well which will determine the label format for the shipping. Label format restriction is there for business flow as 21(ship confirm flow).

So when the shipping done using oracle form, it does trigger the shipping label.

But when this ship confirm was triggered using the same user and responsibility through the below API, it does not trigger the label.