Row level locking - Lock objects

Experts,

I am aware that we can do row level locking by creating a separate lock object for the table. I am calling enqueue_**** FM to call lock object created for my custom table. I am passing lock parameters & see that when a record does not exist in my custom table still SUBRC returned is 0 by lock FM.

As per my understanding, SUBRC should not be 0 as the record does not exist in table to be locked.

Please share your valuable inputs.

BR

Aspire