SPI Clock Pin No Output*
 

For my design, I'm utilizing an STM32F103CBT7 with HAL functionalities and a 72MHz system clock.
SPI 1 is set to Master, with a 16-bit data width and a data rate of 18 MBits/s.
There is a data bit on the MOSI pin when sending data out, but no Clock pulse on the SCK pin.
I'm stumped as to what's wrong.
Is there anything you could suggest?