I'm being charged $125. Is this normal or should I insist on this service being free as advertised?

You can view your fees by clicking on the "Tax Tools" option on your left menu bar, then choose "Tools", then "My Fees". If you feel your fees are not correct, please click on the "Help with My Fees" option at the bottom of the "My Turbo Tax Fees" screen for suggestions on how to reduce your fees.

Somehow you upgraded to the LIVE expert help feature for higher cost.  How to remove Turbo Tax Live.  There are 2 different ways to remove Live depending on how you added it

https://ttlc.intuit.com/community/downgrading/help/how-do-i-remove-turbotax-live/00/27312

How to see your fees

https://ttlc.intuit.com/community/charges-and-fees/help/how-do-i-review-my-fees-in-turbotax-online/00/26353

For help with fees

https://ttlc.intuit.com/community/charges-and-fees/help/what-can-i-do-to-reduce-my-fees/00/26051

Then to go back to a lower version or the Free Edition you can try to clear and start over  https://ttlc.intuit.com/community/using-turbotax/help/how-do-i-clear-and-start-over-in-turbotax-online/00/26444