Why is my Georgia State tax return was changed to pending after filing. It is more than 3 days now.

At this time of tax season it is not unusual that a tax return will be pending for over 72 hours.  You will need to be patient, it should be accepted by the state shortly.

See this TurboTax support FAQ for Pending - https://ttlc.intuit.com/turbotax-support/en-us/help-article/tax-return/pending-mean/L6PeeDJeH_US_en_US?uid=lggm8ct2

If you filed your federal and state returns at the same time, your state return may not start processing at the same time as your federal. It's not unusual for state returns to remain in a pending status for several days after a federal return has been accepted. Please see the TurboTax FAQ here.

@shk_shk08