Yeah you’re probably entering the Expedia PNR instead of the TK one. Look for the where it says Turkish XXXXXX. That will be your TK record locator.

Otherwise go to “your online itinerary” link from your email. It will take you to your booking in the Expedia website and your reservation. There’s a section that says “Ticket No” and just before each name in the reservation there would be a 13 digit number starting with 235. That’s your e-ticket number.

But since you’re saying this isn’t your first rodeo... I assume you know the difference between Expedia PNR and airline PNR. So it’s in all likelyhood a TK error in the website and it’s happened to me before as well. Or you haven’t been ticketed yet. Your itinerary link will have the answer.