There is nothing to "fix" for now---just let the IRS process the return.

We do not know if entering the wrong stimulus amount will delay your refund --- or for how long if it does.   The IRS has not offered any guidance yet on how they will handle returns that have incorrect stimulus amounts entered.  We all just have to wait and see.  You are among many people  who were confused and entered incorrect stimulus amounts, or who filed early and then received a check.   

Any updates on this? 

You do not need to amend your return due to any stimulus misstatements on your tax return.   The IRS has published they will review and catch those errors and notify you of any corrections.  See questions G2 and G3 here.   

So for instance I mistakenly entered the 2nd and 3rd payment instead of the 1st and 2nd, which increased my refund, they will catch it and let me know? I do not need to do anything?

Thanks,

H

Yes, they will catch it, adjust your refund, and send you the appropriate amount along with a letter of explanation.   This will require manual processing which will mean your refund will take a bit longer.  Perhaps quite a bit longer, unfortunately.  

@uniqe2