What is the appropriate action to take towards a colleague who insulted me in front of students? And how do I deal with the delay of my master's thesis due to the obstinacy of the supervisors and the manager who hates me, and are there specific supplications for that?

Patience, forgiveness, overlooking ill-treatment, and turning away from it are recommended. To deal with an offender, it is advised to conciliate him and show kindness to him, because kindness transforms an enemy into a friend, as Allah Almighty says: "Repel evil with that which is best, and lo, he between whom and you was enmity will become as though he was a devoted friend." The hadith (definition) of Aisha indicates the Prophet's (peace and blessings be upon him) conciliation of a man known for evil to ward off his mischief, where he said: "Indeed, the worst people in rank with Allah on the Day of Resurrection are those whom people abandoned due to fear of their evil." It is also advised to comply with the offender's instructions unless they involve disobedience (to Allah) or a violation of work regulations, while supplicating to Allah to avert evil from him and bring him good.