Intel i5-9600K Overclocking issues

[winchester]

hey 

i'm trying to overclocking my cpu to 4.6 but i couldn't , when i finished of the bios i restart my computer and i opened the task manger and i saw my cpu speed it doesn't change it 4.29 

 

i did overclocking to my cpu before 6month to trying it  and i sucess

but now i couldn't  

help me . 

and sorry the english is not my mother language

my motherborad "msi z390"

[winchester]

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