I want refile, in my file there is no RETURN MANAGER so could not find the refile button as well

[TurboTaxBrenda1]

If you have already filed your return and received your Notice of Assessment then you can ReFile. Please click the following link. Make sure that whatever it is that you need to fix on your return hasn't already been done by CRA, you will see any changes or updates on your NOA. 

Here is how to ReFile/ do an adjustment on your return.