Is there a reason why I haven't got my tax refund yet?

Go to this IRS website for operational status - https://www.irs.gov/newsroom/irs-operations-during-covid-19-mission-critical-functions-continue

As of May 28, 2021, we had 19,000 individual tax returns received prior to 2021 in the processing pipeline. Including current year returns, as of May 28, 2021, we had 18.1 million unprocessed individual returns in the pipeline. Unprocessed returns include those requiring correction to the Recovery Rebate Credit amount or validation of 2019 income used to figure the Earned Income Tax Credit (EITC) and Additional Child Tax Credit (ACTC). This work does not require us to correspond with taxpayers but does require special handling by an IRS employee so, in these instances, it is taking the IRS more than 21 days to issue any related refund. If, as a result, a correction is made to any RRC, EITC or ACTC claimed on the return, the IRS will send taxpayers an explanation. Taxpayers are encouraged to continue to check Where’s My Refund? for their personalized refund status and can review Tax Season Refund Frequently Asked Questions.

Once a tax return has been Accepted by the IRS or a State, TurboTax receives no further information concerning the tax return or the status of any tax refund.

If accepted by the IRS use the federal tax refund website to check the refund status - https://www.irs.gov/refunds
If accepted by the state use this TurboTax support FAQ to check the state tax refund status - https://ttlc.intuit.com/questions/1899433-how-do-i-track-my-state-refund

After the tax return has been Accepted by the IRS (meaning only that they received the return) it will be in the Processing mode until the tax refund has been Approved and then an Issue Date will be available on the IRS website.
See this IRS website for federal tax refund FAQ's - https://www.irs.gov/refunds/tax-season-refund-frequently-asked-questions
If over 21 days since being Accepted by the IRS and the tax refund is still Processing you can call the IRS and speak with an IRS agent concerning your tax refund.
Call the IRS: 1-800-829-1040 hours 7 AM - 7 PM local time Monday-Friday
When calling the IRS do NOT choose the first option re: "Refund", or it will send you to an automated phone line.
So after first choosing your language, then do NOT choose Option 1 (refund info). Choose option 2 for "personal income tax" instead.
Then press 1 for "form, tax history, or payment".
Then press 3 "for all other questions."
Then press 2 "for all other questions."
- When it asks you to enter your SSN or EIN to access your account information, don't enter anything.
- After it asks twice, you will get another menu.

Press 2 for personal or individual tax questions.
Then press 4 for all other inquiries
It should then transfer you to an agent.