Hi Ricky,
SAM downloads data from the The Utility Rate Database (URDB) at
openei.org/wiki/Utility_Rate_Database.
The database generally includes data from utility rate sheets, and not always net metering and other regulations that determine the sell rate or net metering option.
Until the URDB is updated, you will need to enter the appropriate sell rates for NEM 3.0 yourself.
In general, you should always review the data imported from the URDB to make sure it matches the rate sheet data.
Best regards,
Paul.