Sforno on Genesis 30:20/ספורנו על בראשית ל׳:כ׳

1Elokim has given. Hashem gave her Yissachar in reward for her first effort in giving Yaakov her maidservant and He gave her Zevulun in reward for her second effort in trading the jasmine flowers for an additional night with him.

2A goodly portion. She was deserving of reward because her only intention was to increase Hashem’s honor.