My cpu isn't recognised by my motherboard

[Rares Dorneanu]

So i bought this amd athlon II x4 559 and a GA-MA78LMT-US2H rev 1.3 gigabyte motherboard.
for the first two weeks everything was fine cpu was recognised but one day when i started my pc it was showing me that i have an amd phenom II x2 B59. I have restarted the pc and updated my bios to the latest version but i have the same problem. what should i do?

 

[CountMike]

Check your Core Unlocker or whatever goes by that function in Your BIOS.

 

[Rares Dorneanu]

Check your Core Unlocker or whatever goes by that function in Your BIOS.

thanks for the answer it worked