I just bought versa full and already an error

It's an MS3 2008 Europe.
I can't flash or simply recover my ecu to original state. I have an error. How can we proceed ? My new race car is already tuned with versa but not by me and i don't know the tuner. I have obdlink sx, tactrix, AVDI official full for j2534 and multiple other official tools for passthru and remap.
Can you do something about that ? I haven't time for remap with winols and this horrible official ktag.
Thx and have a good day !