What is a ruling on a person who thinks that there will be another prophet after Judgement Day, when Allaah supposedly would create a new Earth? Quran 14:48 and 50:15

All perfect praise be to Allaah, The Lord of the worlds. I testify that there is none worthy of worship except Allaah and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and Messenger. 

There are abundant texts in the Quran and Sunnah indicating that there shall be no prophet after our Prophet Muhammad, sallallaahu ‘alayhi wa sallam. There is no relation between the two cited verses and what that person believes. In fact, whoever believes that there shall be another prophet after Prophet Muhammad, sallallaahu ‘alayhi wa sallam, the seal of Prophets, is feared to have committed Kufr (disbelief) for denying what is in the Quran and Sunnah in this regard. That person should be edified on this matter, and the truth should be made clear to him with evidence. Allaah, The Exalted, says (what means): {Muhammad is not the father of (any) one of your men, but (he is) the Messenger of Allaah and last of the prophets. And ever is Allaah, of all things, Knowing.} [Quran 33:40]

Jubayr ibn Mut‘im reported that the Prophet, sallallaahu ‘alayhi wa sallam, said, "I am Muhammad, I am Ahmad, I am Al-Maahi (the effacer, the one by whom Allaah wipes out disbelief); I am Al-Haashir (the assembler, after whom the people will be gathered on the Day of Resurrection); and I am Al-'Aaqib (the last in the line of Prophets, and no Prophet shall succeed me)." [Al-Bukhari and Muslim]

Thawbaan narrated that the Prophet, sallallaahu ‘alayhi wa sallam, said, “There will arise thirty impostors in my Ummah (community), all claiming prophethood; but I am the seal of Prophets, and no Prophet will come after me.” [Abu Daawood and others]

Moreover, Abu Hurayrah reported that the Prophet, sallallaahu ‘alayhi wa sallam, said:

“I have been given superiority over the other prophets in six respects: I have been endowed with the gift of pithy and perfect speech (words which are concise but comprehensive in meaning); I have been granted victory owing to terror (breathed into the hearts of enemies); the spoils of war have been made lawful to me; the whole earth has been made clean (means of purification) and a place of worship for me; I have been sent by Allaah to communicate His Divine message to all creation, and the line of Prophets has come to its final end in me.” [Muslim]

Al-Qaadhi ‘Iyaadh wrote:

“Whoever claims prophethood after our Prophet, sallallaahu ‘alayhi wa sallam, or believes that it is possible that someone would attain the refined status of prophethood through spiritual purification of the heart, like philosophers and extremist Sufis think, we declare him a disbeliever. The same applies to whoever claims to receive divine revelation. All such imposters are declared disbelievers because the Prophet, sallallaahu ‘alayhi wa sallam, clearly stated that he was the last in the line of Prophets and that there would be no Prophet after him...” [Ash-Shifaa' 2/1070]

Allaah knows best.