In order to assist you properly, we will need you to clarify.

• Which TurboTax software are you using, Online or Desktop?
• Is it for a NETFILE return (for an adjustment)?

Thank you for choosing TurboTax.

I am using online 

It is for Netfile. 

I entered an incorrect amount in RRSP contribution, how can i go back and correct it?

I'm using desktop and i haven't filed the return yet. I want to amend it first.

I made a mistake and entered an RRSP contribution in error. How do I go back and fix it before I file the return?

I'm using  Desktop, Standard package

You go to review your form the you go to RRSP. It should show what you are eligible to deduct you select continue. The next page should be RRSP paid you can change the amount on this page. Hope this helps.