@elanchezhiyan,
Can you please try setting the browser zoom and scale option under display setting to 100%?
In case you are still facing the issue, kindly create a JSFiddle reproducing the issue and share it with us along with Browser(browser name and its version) and OS details so that we can run it locally to understand the scenario better and help you out.
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Indranil Singh Deo
Team CanvasJS