Why didn't you receive the refund? You should wait to amend until you get it. You may have to switch to the Desktop program to override the refund. Ask support for the desktop program.
Contact Customer Service
5am-5pm Pacific Time
Monday-Friday
https://support.turbotax.intuit.com/contact/
What is the Turbo Tax phone number
https://ttlc.intuit.com/community/using-turbotax/help/what-is-the-turbotax-phone-number/00/25632
