The Rebbe urges the writer not to seek a new position, but to strengthen his trust in Hashem and stay in his current role. Feelings of discouragement stem from the yetzer hara and should be countered through learning Chassidus, joyful farbrengens, and serving Hashem with true happiness.
https://www.torahrecordings.com/rebbe/004_igros_kodesh/sivan/1042