While in the process of amending your return, the easiest thing to do would be to delete the Form 1099-MISC altogether and start again with entering it fresh.
Delete the Schedule C as well, unless you had other income for a business.
There is not a way to just move the Form 1099-MISC from the Schedule C to line 21. You should go through the questions related to the 1099-MISC entry in order to have it reported correctly.
