Complaining is of 3 levels:
The best: Complaining to Allāh about your own soul
The worst: Complaining to the creation about Allah
The middle: Complaining to Allah about the creation
Ibn Al-Qayyim
Complaining
The Prophet ﷺ: "Whoever follows a path in pursuit of knowledge, ALLAAH will make easy for him a path to Paradise.” (Sunan Ibn Majah, 225)