Users have User_Group of BSP INC but there is no BSP_LOB_GRP entry with this value

BSP_LOB_Grp_Lookup has NULL in BSP_LOB_CD column so it cannot be matched to BSP_LOB_CD in IMPACTED_LOB table

This basic query will join the three tables as you specified but may not work due to the above.

SELECT up.User_Id, up.User_FullName, up.Email, up.User_Group ,i.Event_ID

FROM User_Profile up

JOIN Group_Lookup g ON g.LOB_GRP = up.User_Group

JOIN Impacted_LOB i ON i.LOB_CD = g.LOB_CD