"a few years ago..." You are not giving us much information to go on. TurboTax receives no information after you file your tax return, so no one at TT knows what happened to your refund. First, you need to figure out which refund you are missing. Check your past tax returns, your banking records, your transcripts and your IRS online account to help you figure that out.
Then you can try having the missing refund traced.
https://ttlc.intuit.com/community/prior-year-return/help/how-do-i-access-my-prior-year-return/01/270...
Many people have multiple TT accounts and forget how to access them. Log out of the account you are in now.
Account Recovery
https://ttlc.intuit.com/questions/1901535-forgot-your-turbotax-online-user-id-or-password
You can get a free transcript of your past returns from the IRS:
https://www.irs.gov/individuals/get-transcript
Check your IRS account
https://www.irs.gov/payments/view-your-tax-account
Have a payment traced
If you need to trace a payment that the IRS says has been issued to you, mail or fax a completed IRS Form 3911, Taxpayer Statement Regarding Refund.
**Disclaimer: Every effort has been made to offer the most correct information possible. The poster disclaims any legal responsibility for the accuracy of the information that is contained in this post.**
