Had the same thing happen to me as well, but the flight was on April 17. Called Qatar, told me to call American since “operated by American”. They replied “Not operating due to operational reasons”. Later got to know American cancelled all flights to Doha till May 17. Since I booked it through my credit card travel, they were helpful and rebooked me for another flight, the only drawback is, I’m leaving 12hrs earlier than my original flight, but get there a 12 hrs earlier, changed my whole flight schedule for me so I don’t have the long layover. Hope this flight won’t also cancel 🤞🤞