Flying Blue Helpdesk for Qatar: 

Email: Servicedesk@flyingblue.ae 
Phone: +974 4445101 
Fax:   +971 (04) 602 5393  

Postal Address: 
Flying Blue
KLM Royal Dutch Airlines
P.O. Box 1696 Dubai, UAE 

During UAE Public Holidays you can contact the central Helpdesk: 

Phone: +33 1 58 68 68 68
Fax: + 33 1 58 68 68 00 Postal Address:
Flying Blue
F-94852 Ivry-Sur-Seine cedex
France