Is there a fee for having a Turbo Tax "expert" call me back to discuss my problem?

There is no fee for simple phone support.

The following article explains the different ways to contact support. 

https://ttlc.intuit.com/replies/6386875

I paid to download the 2018 Home and Business Version of TurboTax.  When I tried to fill out a tax return (Form 1040), it would not let me enter the amount of Estimated Taxes that I paid for 2018 to the IRS on Form 1040-ES.  Can you tell me why the software program is not allowing me to enter the estimated tax payments?  When I click on the "Update" button, the screen just goes blank and never downloads anything.