Selenium Automation Script using java

I need a solution for my automation script.I used a for loop for clicking a button no of times. Every time it will click and after that excel sheet will be read for passing the values to the text boxes.When this operation is finished again button will be click with new value.But the new value is append with the previous value.I need to clear that previous values.This is happening when i am using for loop for clicking that particular web element.Is there any solution to clear my previous data every time it will the button.