The measurement in that file is at 275 dB, so it is off the top of the graph. You can restore a more normal level using the Offset adjustment in the graph controls, add -200 dB to the data (for example). To fix the problem for further measurements you need to redo the SPL Calibration.
I am back. Solved graphics panel with your help. Now have new problem. After several measurements, in taking the next measurement I get what looks like a red stop sign with this message- "The soundcard did not provide any input data, please check that it is connected. I am using a UMIK mike and put in the file when asked.