Try clearing your browser's cache and deleting your cookies, then try picking up where you left off. See the TurboTax Help articles How to clear your cache and How do I delete cookies? for guidance.
If this doesn't help, see the TurboTax Help articles Why am I stuck in a loop in the File section of my return? and State install/e-file update loop: State not installed after installation or TurboTax needs to update..., if appropriate, for guidance.
