The picture that you inclosed is an incomplete graph. You have cut off all of the axis values, which are what will give the clues as to how you have actually setup the graph.
But, I will assume the issue is, that you have defined the 3 graphs by using a Y Grouping of a variable that has 3 different values. Graphs setup with groupings maintain the axis values for all 3 graphs. To setup a chart with separate setable axis values, you will need to set graphs us as separate variables on the graph. For documentation on these options read the section on the Graph Builder in the Essential Graphics book
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Jim