Cheat Engine

[TinyWounds]

I am trying to make an exp modifier for Tales of Legendia on pcsx2 emulator, I can find the exp address and what writes to it. The writer is mov [ecx],edx now if I inject a simple addition code add edx,100 it will work perfectly and add an 253exp on top of battle exp the problem comes when after a random number of fights the code will move back to mov [ecx],edx at a different address but it will not use my injection, ignoring it as if it doesn't exist. After searching for a reason I realized mov [ecx],edx has so many duplicates I cant even count them all but none of them will write to the exp address unless I try injecting some kind of code.

A solution or explanation would be very much appreciated

Screenshot:
308E84BA - 89 11 - mov [ecx],edx //original exp writer
028A0006 - 89 11 - mov [ecx],edx // my little code to add 253exp
30A1AD5A - 89 11 - mov [ecx],edx // on the second fight, ignoring my code