why does it say my payment is complete but still haven't received my refund

In the community we do not have access to information about your refund. 

If you want specific information you will have to call TurboTax Customer service.  Here is a link:  Turbo Tax Customer Service 

Where's my Refund is the most accurate information as it is directly from the IRS. Once your return is filed, TurboTax has no control over the processing of your return or the release of your refund. The TurboTax site can only update if the information is provided for the software to update. This doesn't always happen so the information shown on TurboTax could be behind.

The IRS is who is issuing your refund, not TurboTax, so the IRS has the most up to date information. 

Here are a couple FAQs to track your refund:
When will I get my federal tax refund?
How do I track my state refund?
Why does Where's My Refund say "approved" but TurboTax still says "accepted"?

Why do some refunds take longer than others?

What if my IRS refund is taking longer than 21 days?