Programming AD9837 over spi usint STM32h750 controller

Hello, im new for embedded coding,  Im trying to communicate AD9837 device using STM32 controller through SPI for generating 1khz SIne Wave. Im using following registers, Controlregister(0x2000), Frequency0Register(0x7333),frequency1register(0x4333), phase register(0xC000),resetregister(0x2000). I want 1MHZ frequency but, Im getting 625khz.. even im giving different frequencies im getting Constant frequency i.e. 625khz.