If the Recovery Rebate Credit worksheet isn't letting you continue, you may need to clear your cache.
Your browser stores recently visited webpages as temporary files in a cache, which enables the pages to load more quickly when revisited.
However, a full or corrupted cache can cause problems in TurboTax, so sometimes you need to clear your cache (that is, remove these temporary files).
Here are the official instructions for the most popular browsers:
Apple's official support site doesn't appear to contain instructions for clearing the cache in Safari. Your best bet is to search the Internet for clear Safari cache or similar search terms.
If your cache isn't the issue, it might be best to delete it and start again.
To get to the Recovery Rebate Credit section of your return, use the Search function and type in “stimulus”. You will see a “jump to” link at the top of the search results. By selecting this option, you can get to the Recovery Rebate Credit section quickly.
Here's a TurboTax article that explains the Recovery Rebate Credit.
