With PXLineNumber the number will only be sequential if no line is deleted from the document lines. The counter is kept on the document header DAC and is incremental. 

@aaghaei  I know that part. I have not deleted any line item while creating this document. 

I am not so sure about no line is deleted. Any time + is clicked in grid or a line is been added by line feeder, a new sequence is being added whether you save or not. It considered InsertedDeleted in record statuses. Not sure what you are going to do but this sequence is serving as an element in PK and should not be used for any other purposes.

@aaghaei If only two times + is clicked them also the Line Nbr and 1 and 3. I request you try that on your system and check if it behaves the same or different. I want to fetch data on other screen based on line number and this un-predicted behavior is not letting me do that.

Thanks

I have developed codes on multiple custom screens and it behaves as designed. For sorting or fetching purpose however if it is 1 6 9 won’t make any difference. I am not sure with this kind of vague question without any context anyone can be helpful. 

Hi @param2022 were you able to find a solution? Thank you!