It is not compulsory upon Almighty Allah to send Prophets. Through His Grace, He sent down Prophets for the guidance of the people
Sayyidatuna Aamina Radi Allahu Tala Anha said When the Holy Prophet (SallAllahu Alayhi wa Sallam) was born, I saw that three flags were hoisted - one in the east, one in the west and one on the roof of the Kaba.
(Khasais al-Kubra, Vol. 1, Page 82, Published from Dar al-Kutub Ilmia)
Sunni Dawate Islami is an international, non-political and purely religious movement. It promotes the propagation of the true beliefs of Islam under the teaching of the true sect of Ahle Sunnah Wa Jama'ah.