Linear Referencing - Failed to Flip

I am editing a Linear Referencing FC. One of the segments is not oriented correctly. After I flipped it, its direction appears to be right. Then, I used the Identify Route Location Results tool to check a point closed to the arrowed-end on the segment. The results display
Measure: 49669.10
Min. Measurement: 49469.1
Max. Measurement: 54013.1
Measure Value: Strictly Increasing
Parts: 1
Unknown Measurement: False
Actually, the point I clicked should show the Measure Value near the Max. Measurement. I tried to re-set the From/To values. But no matter how I do, the segment can not be flipped correctly. Is there some trick I missed? Thanks if you can share your experience.