I added bc renter's credit by mistake. When I am going back unchecking that box, it is not removing the refund of $400 from my return. How do I do that?

If you have not yet submitted your return to CRA, it is probably due to your cache and memories. Please try clearing your web browser's History, including the Cache and Cookies to solve this issue. Follow the instructions on How to clear my browser cache ? 

Once done, please close and reopen your return to see if you are still facing the same challenge. 

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