If your passport differs from your nationality then some countries are now requiring presentation of both; welcome to the new world order. It isn't an airline decision. It sounds like you fell into this category. One way to avoid it is to use the passport from your own country The other condition that sometimes occurs is known forged passports -- this happened to Australians in mid-1980s when a large number of blank passports were stolen and later repurposed. Additional checks were required for passports that matched the stolen stock. If this is the case you may wish to renew your passport early to avoid endless future hassles. Again not an airline decision but up to the country of arrival.