Sonic Unleashed - NTSC/U PS2 ARMAX Codes

Hi! First post here, and this is technically a bump to a five-year old thread concerning the ARMAX codes for Sonic Unleashed for the PS2.

First off, the disc tells me that there's a game already with the name taken when I entered in the master code, when I clearly don't have it in there. Here's what I have:

-SOCOM: U.S. Navy SEALs (Demo)
-Sonic Heroes
-Sonic Mega Collection Plus
-Sonic Riders
-Soul Calibur II

I have tried it with my Memory Card, and it has resulted in the same outcome (the previous attempt was with the data loaded from my USB drive). I was wondering if I could get a different master code... DX