Only the OLDEST record is being updated.

Only the OLDEST record is being updated.

All,
When running the script below the only record that is updated is the oldest record in the DB.What have I done wrong?

1. if(input.Returned_to_ATC  ==  "YES")
   {
       list = MWD_Eye_Calibration_Testing[Serial_Number == input.Serial_Number];
       list.Returned_to_ATC="YES";
   }
   
   
   
   

Screen cap of unchanged data.

Jason Rapp