It is haram. there are scholars who say that the psychics, fortunetellers, seers, etc. have made a pact with the Jinn.
"Say: None in the Heavens and the Earth knows the Ghaib(Unseen) except Allah, nor can they perceive when they shall be resurrected." (al-Naml 27-65)
Those who claim to have knowledge of the unseen future are all fortunetellers and it is proven that the Prophet(Pbuh) said: "Whoever goes to a fortuneteller and asks him about anything his prayer will not be answered from him for 40 days. and if he believes him then he is kaafir because if he believes that he has the knowledge of the unseen, then he has disbelieved in the words of Allah."
Al-Kattaabi said: The Prophet(Pbuh) explained that the reason why the fortuneteller sometimes get's it right is that the Jinn tells him something that he has heard by eavesdropping on the angels and he adds lies to that to embellish what he heard. So occasionally he gets it right but usually it is wrong. Fath al-Baari, 10.219,220
Also every Muslim has a personal Jinn that has knowledge about them from the day that they are born and this information is given to the psychics from the Jinn. This is why it is easier for a psychic can tell the past much easier than the future. But if a person is righteous he will not go to a psychic and a person who submits to the will of Allah and becomes Muslim their personal Jinn which has a weaker will than humans will have to become Muslim too.
Allah knows best.