I’ve seen a similar issue with another return recently and was able to track it down. It looks like Form 2106 is incorrectly populating twice on the California ...
Also walking thru the 1099-S interview twice may clear the error. But I can see on the back end in forms mode where the system is not picking up the answer to q...
This is an error on TTO side. Can you delete the 1099-S and re-enter? Other option would be to download Desktop which is cheaper and go into the gain exclusion ...