Esther 6:3

And the king said, What honour and dignity hath been done to Mordecai for this? Then said the king’s servants that ministered unto him, There is nothing done for him.

Cross-reference

In Genesis 40:23, the butler forgets Joseph — exactly like Mordecai's service is forgotten here. Both suffer delayed recognition after helping someone in power.

Ecclesiastes 9:15 describes a poor wise man who saves a city but is forgotten — a direct parallel to Mordecai saving the king without immediate reward.