If you are looking at a pay stub then ask the employer for a translation/explanation of the entry.  It is still a pre tax contribution according to the IRS. 

If you have not completed the section that asks about your spouse's eligibility for HSA contributions, make sure that's completed correctly. Also check Form 8889 to insure it properly reflects the $4500 allowed limit and shows the $4500 employer contribution (you may have inadvertently doubled it).

I noticed that TT has not updated the HSA limits to 2019 amounts so that's also an issue with yielding the correct result as far as limits.

Yes ... if you are playing with the 2019 program make sure you have entered the correct code in box 12 of the W-2 and completed all the HSA sections  and then WAIT patiently for the 2019 program to be fully operational sometime in January before being alarmed. 

The HSA is handled in 3 parts in the TT program :

First the contribution:

https://ttlc.intuit.com/replies/4557768

https://ttlc.intuit.com/replies/4785646

Next the limitations screen to confirm you are eligible to make the contributions:

Until you complete the HSA portion of the TurboTax interview to establish your eligibility for an HSA contribution, TurboTax will treat the amount entered on the W-2 form as an excess HSA contribution.

https://ttlc.intuit.com/replies/4788059

And lastly any distribution:

https://ttlc.intuit.com/replies/4787864

As of 11/21/2019, 2019 TurboTax has not been updated to use the 2019 HSA contribution limits is still using the 2018 limits.  Until that's corrected, when you enter a $4,500 contribution for someone with self-only HDHP coverage TurboTax will treat $50 as an excess contribution even after you enter the HSA-eligibility information.