Is it true that men are not allowed to groom their beards everyday, like brushing, oiling, adding products etc?

Imam Ibn ʿUthaymīn (may Allah have mercy on him) said: “Al-Tarajjul” refers to grooming the hair by combing it, applying oil to it, and beautifying it. The Prophet ﷺ forbade engaging in tarajjul frequently, except occasionally, meaning every other day. This is because when a person becomes preoccupied with perfecting their appearance and it becomes their greatest concern, it distracts them from more important and greater matters. However, if one practices tarajjul occasionally—such as grooming one day and skipping the next, or grooming one day and skipping two, or grooming two days and skipping one—then this indicates that it is not of such importance to him that it distracts him from what is more significant.