On Save button validation spot
Tcode : SE19
BADI Name : LE_SHP_DELIVERY_PROC
Implementation Name : ZDELIVERY_SAVE "Any name you can give
Enhancement Name : ZDELIVERY_SAVE_VALIDATION "Any name you can give
Under Method : SAVE_DOCUMENT_PREPARE
Like Below you can create
On Post Goods Issue (PGI) button validation spot
Tcode : SE19
BADI Name : LE_SHP_GOODSMOVEMENT
Implementation Name : ZDELIVERY_PGI "Any name you can give
Enhancement Name : ZDELIVERY_PGI_VALIDATION "Any name you can give
Under Method : CHANGE_INPUT_HEADER_AND_ITEMS
Same as above screen short you can create for PGI button validation