Weak SPI clock signal at 12MHz on STM32L4A6ZGT

[generallishin]

Below is the analog waveform for the SPI clock at 12MHz. How to improve the strength of this signal and get p-p 3.3V SPI clock at 12MHz ?

"GPIO SPEED" set to the "VERY HIGH" setting. Apart from this, is there any additional settings required ? 

[LCE]

GPIO speed very high is a good start.

Have you checked that you are using the correct Mode and Alternate Function for that specific SPIn peripheral?

[generallishin]

Yes all that is configured correctly. Communication works fine at lower frequencies. No problems with SPI other than the strength of the clock signal at 12MHz. 

[LCE]

Okay, then check the load next, and remove any loads / connections.