You may need to clear your browser's cache and cookies as sometimes this can keep TurboTax Online from functioning properly.
Please see the below FAQ's for assistance:
Clear Cache: https://ttlc.intuit.com/community/troubleshooting/help/how-to-clear-your-cache/00/26135
Delete Cookies: https://ttlc.intuit.com/community/troubleshooting/help/how-do-i-delete-cookies/00/25978