You are not following the directions I wrote. You did not fit a straight line to the data between 200 and 400 MPa. You did not subtract the offset from the strain data.
You selected 495 MPa for the Yield Strength (I would have chosen 446 MPa). But you did not type 495 in cell C2 of the Multilinear Plasticity material model. Using 100 MPa is a mistake.
Follow the directions in the warning and keep 10 points of plastic strain instead of every point in the spreadsheet.
Upload your spreadsheet to your Google Drive or other file sharing sites and paste the link in your reply and I will check your work.
I prefer to communicate on this site. It is better than email for me.
You are navigating away from the AIS Discovery experience