I received a CP23, is there any way to verify that the amount they sent is correct with Turbo Tax?

That has to do with a difference with the estimated payments you made ... are they correct ? 

https://www.irs.gov/individuals/understanding-your-cp23-notice

If you want to "check it out"  then use the amendment option in the TT program  to make changes to the return to reflect the info on the notice. 

Q. I received a CP23, is there any way to verify that the amount they sent is correct with Turbo Tax?

A.  Simple answer: No.

Theoretically, you could enter the state's changes, in TurboTax, to see the effect. But, If you start entering changes in the online software, it overrides, the original return.  So if you try that,  be sure to first save a paper and/or PDF copy of your original return. 

Desktop (download) TurboTax is better than online for experimenting with test returns. You can make copies and can manipulate them without altering your original.