Were the 2 charges identical? You shouldn't have been charged twice for the same product, unless you upgraded or added something the second time like a state return.
Phone TurboTax Support and ask them to either explain it or to refund your duplicate charge.
If you get a voice menu, say "billing issue."
Support hours are 5AM-5PM Pacific, Mon-Fri this time of year.
FAQ: What is the TurboTax phone number?
https://ttlc.intuit.com/community/using-turbotax/help/what-is-the-turbotax-phone-number/00/25632