Trend chart and timeline not functioning

I am trying to use this chart which works fine with the data in Google docs. However, when I paste the chart data into the plugin I get the error message:
“Time line
The required data format for the Time line doesn’t match the current data.
The first column should contain dates. Subsequently, all columns should contain numbers or text. Each numeric column may be followed by one or two text columns.
Here’s an example: …”

This is the format of the data I am entering >>

31-Jul-2004 98.8 95.78
31-Aug-2004 98.8 95.78…

This data, without editing, works fine to produce a line chart so not sure why this would be? Hope you can help. Thanks.

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