See this TurboTax support FAQ on amending a 2014 tax return originally completed using TurboTax - https://ttlc.intuit.com/questions/1971653-how-do-i-amend-change-or-correct-a-2014-return-in-turbotax
You will need to contact TurboTax support so they can push a 2014 Mac installation file to your download account so that you can amend the 2014 tax return. Support is closed on the weekends after tax season.
See this TurboTax support FAQ for a contact link and hours of operation - https://ttlc.intuit.com/questions/1899263-what-is-the-turbotax-phone-number
To contact TurboTax customer service/support use their contact website during business hours.
Submit your question/problem during business hours and then use the option for Call (a phone number will be provided for Call) to speak directly with a TurboTax agent -
https://support.turbotax.intuit.com/contact/
Note: The Call option will not be available when TurboTax Support is closed.
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