Since the other tax preparer has filed your return, you will need to amend. When you amend you can include the 14157 and 14157a as well as the documents TurboTax will instruct you to send. Putting the 14157a on the top.
The IRS will have the original return and will need the amendment as a correct version. Mail to
Attn: Return Preparer Office 401 W. Peachtree Street NW Mail Stop 421-D Atlanta, GA 30308
Open this TurboTax
link and follow the instructions to amend your tax return.
https://ttlc.intuit.com/questions/1894381-how-to-amend-change-or-correct-a-return-you-already-filed
The following IRS
link is very helpful in understanding the amendment process.
https://www.irs.gov/newsroom/amending-your-tax-return-ten-tips
