What should I do for my supplication to marry my colleague to be answered? Have I done something wrong, or is God displeased with me? And what are the recommended supplications in this situation?

Familiarity between non-mahram men and women is a gateway to temptation. It is permissible for a woman to offer herself in marriage to a righteous man, provided certain conditions are met. It is also permissible for her to supplicate for marriage to a specific man, or to use righteous deeds as a means of seeking intercession (tawassul). However, it is preferable to supplicate for marriage to a righteous man without specifying an individual, because what Allah knows is best. Allah Almighty says: "And perhaps you dislike a thing and it is good for you; and perhaps you love a thing and it is bad for you. And Allah knows, while you know not." (Quran 2:216). One should be cautious of rushing the outcome of the supplication or abandoning it, for Allah responds as long as the servant does not hasten. The response to supplication comes in one of three ways: either the supplication is answered immediately, or it is stored for the Hereafter, or an equivalent evil is averted.