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eDream ticketed airfares have been cancelled by themselves (travel agent == eDreams). Majority of people have confirmed this situation. Likely due to FX rate was 'unfair' to them.
Direct issued tickets by Qatar are fine.

Visa Currency Exchange Rate Calculator: https://usa.visa.com/support/consumer/travel-support/exchange-rate-calculator.html
Mastercard Exchange Rate Calculator: https://www.mastercard.com/global/currencyconversion/
AMEX is reported to use the FX rate the day before -OR- uses Oanda. So be wary (unconfirmed, but reported a few times)

To pay directly in your home currency (DCC) on Qatar's site, you will need to use Mastercard or Visa. The option will show up once you've filled credit card number. The exchange rates are provided by Monex Financial Services for the day of the transaction +3% fixed conversion charge

Airline Information
Qatar (QR) does not allow short checking of bags on layovers (<24 hours), for any reason. If for convenience purposes you wanted a bag for a connecting flight later on (DOH-CAI or elsewhere), DO NOT CHECK-IN THE BAG.