Oh yes, I have seen posts about blank screens in Mac. What kind of 1099? Maybe you can enter it using Forms mode.
Otherwise to use the Online version you would have to start a new Online return and manually recreate your original filed return and pay for it (use your code). Then when it matches every line you can amend. Say you want to mail it and print it out so it thinks you filed it. How to Amend the current year
https://ttlc.intuit.com/turbotax-support/en-us/help-article/tax-return/amend-federal-tax-return-curr...
You will have to mail the amended return since you didn't efile the original from the Online version.
