Pretty straightforward. If you have a QR code... By all means use that. Buying the tickets online pretty much eliminates the line. On a personal note... I don't like paying the convenience fee
If I were, I'd call and actually speak to someone. If you don't call, you may want to print it out - making sure not to fold on the code(s) - and show the print out at the showing. You should have received instructions when you bought the ticket. If not, call. Hope this helps.
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