Track increase effort in Sprint Backlog
We are following Agile development methodology. As a SCRUM master, I am maintaining the Sprint BackLog. I want to know what is the best practice to accommodate any increase in effort for a particular task in the middle of a project.

For example, I am doing ABC task and in the starting of the sprint I have estimated that it requires 10 hrs to complete it, but on the second day I realized that it requires 20 hrs, so how will i update the Sprint Backlog.
Track increase effort in Sprint Backlog
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We are following Agile development methodology. As a SCRUM master, I am maintaining the Sprint BackLog. I want to know what is the best practice to accommodate any increase in effort for a particular task in the middle of a project.

For example, I am doing ABC task and in the starting of the sprint I have estimated that it requires 10 hrs to complete it, but on the second day I realized that it requires 20 hrs, so how will i update the Sprint Backlog.