Select to LIKP using external delivery number (LIKP-LIFEX)

Hello,

I'm facing a strange issue here with a selection to LIKP table.

I have a query to LIKP table using  external delviery number (LIKP-LIFEX) as a select-option and it is not working.

I have delivery A with LIKP-LIFEX = B

When I go to SE16N, LIKP, put B as LIKP-LIFEX and execute, it returns nothing

While if I put A as LIKP-VBELN, it returns the delivery with B as external delivery number.

Does anyone have this issue before? Any help would be appreciated

Thanks,

Pho