I filled my return an the 9th and acceptance is still pending today (13th) why is this?

MY RETURN IS IN PENDING—what does that mean?

Did you e-file?  Did you click that big orange button that said “Transmit my returns now?”  If so, your return is now in “pending” on a server.  Do not try to change anything while your return is in pending.On January  23 the IRS will begin to accept/reject e-files.   Watch your emails—including your spam folder—for the notice about whether your e-file has been accepted or rejected.  If your return is rejected you will be able to make corrections before re-filing.   If the return you e-filed is accepted you will have to wait until it has been fully processed and then amend it to fix any mistakes or omissions.  It has been taking the IRS six to nine months—sometimes longer—to process amended returns.   If you e-filed your state return there will be another email later that tells you if the state was accepted or rejected.

WARNING:   Do not try to change anything on your return while it is pending.

https://www.irs.gov/newsroom/irs-sets-january-23-as-official-start-to-2023-tax-filing-season-more-help-available-for-taxpayers-this-year

It is pending and will remain pending until the IRS starts accepting tax returns on January 23, 2023.

Because the IRS  has not opened yet.  They will start taking returns on Jan 23 so your return will wait at Turbo Tax until then.  We always tell people not to file early.  You may get another W2 or 1099 form you weren't expecting.  

The IRS will not begin to process returns until January 23.