Go back to the My Info section for your personal information.  Did you select that you can be claimed as a dependent?

Did you accidentally click the boxes that asked if you could be claimed by someone? This is the very first entry page in Personal Info.

That's a good thought -  I could have accidentally selected "you can be claimed by someone else", but that's not it. 
I went back to the  personal info screen, all the checkboxes are clear, I re-selected "None of the above"  (not blind, not deceased, no one else can claim as a dependent,  etc).  - and I get the same result under child & dependent care.  "..No ...  because you can be claimed by someone else as a dependent. "  Very strange. 

At this point, I recommend going through the entire My Info section of the program to ensure you didn't accidentally select something that would have triggered the dependent classification.

You can also try to delete the form for the Child & Dependent Care Credit and then start the form again as this may clear the issue as well.

You can delete the form by logging into your TurboTax program.

1. Select Tax Tools in the black panel on the left
2. Select Tools below Tax Tools
3. Select Delete a Form
4. Scroll down until you see Form 2441.  Select delete to the right of this form.

Then to regenerate the credit, you will go to the federal section of the program.

1. Select Deductions & Credits
2. Select Child & Dependent Care Credit
3. You will see a question asking Did you pay for child or dependent care in 2020?  Select Yes.
4. Proceed to answer any questions as prompted.