It may still be a little early to get a final 1099-B. A consolidated 1099 form should be postmarked by February 16, 2021, according to the Internal Revenue Service (IRS).
You might check with Fidelity to make sure it is available for download.
I can't help you with the download if it's not working properly, but I can give you an alternative that is better than manually entering each transaction. You can enter summary totals for each asset sale category. It will require you to mail a copy of your Form 1099-B along with Form 8453 (which TurboTax will generate). To do this in TurboTax Online,
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