I put down a route for a friend of mine which comes to a DONE5:

Carrier Flight
Number Departing Arriving Booking
Code Meals City Date & Time City Time
QATAR AIRWAYS 180 OSL Oslo okt 10, 2025
08:50 AM DOH Doha okt 10, 2025
04:20 PM D N/A
QATAR AIRWAYS 838 DOH Doha okt 10, 2025
07:25 PM BKK Bangkok okt 11, 2025
06:15 AM D N/A
CATHAY PACIFIC AIRWAYS 740 HAN Hanoi nov 23, 2025
11:05 AM HKG Hong Kong nov 23, 2025
02:00 PM D N/A
CATHAY PACIFIC AIRWAYS 155 HKG Hong Kong nov 24, 2025
11:50 PM BNE Brisbane nov 25, 2025
10:30 AM D N/A
QANTAS AIRWAYS 197 BNE Brisbane nov 26, 2025
10:00 PM APW Apia nov 27, 2025
05:55 AM D N/A
FIJI AIRWAYS 254 APW Apia nov 30, 2025
04:00 PM NAN Nadi nov 30, 2025
05:00 PM D N/A
FIJI AIRWAYS 411 NAN Nadi dec 03, 2025
09:30 AM AKL Auckland dec 03, 2025
01:40 PM D N/A
QANTAS AIRWAYS 182 AKL Auckland dec 30, 2025
10:25 AM SYD Sydney dec 30, 2025
11:55 AM D N/A
QANTAS AIRWAYS 27 SYD Sydney feb 05, 2026
12:20 PM SCL Santiago feb 05, 2026
10:55 AM D N/A
AMERICAN AIRLINES 936 GIG Rio De Janeiro mrt 09, 2026
10:30 PM DFW Dallas/ Fort Worth mrt 10, 2026
07:15 AM D Dinner
Breakfast
AMERICAN AIRLINES 115 DFW Dallas/ Fort Worth mrt 10, 2026
09:15 AM HNL Honolulu mrt 10, 2026
12:50 PM D Lunch
Snack
AMERICAN AIRLINES OPERATED BY BRITISH AIRWAYS 6907 SEA Seattle apr 22, 2026
08:20 PM LHR London apr 23, 2026
01:40 PM D Meal
AMERICAN AIRLINES OPERATED BY BRITISH AIRWAYS 7254 LHR London apr 23, 2026
04:05 PM OSL Oslo apr 23, 2026
07:15 PM D Meal

Base fare is euro is 5625, but it hits me with a whopping 2078 euro in taxes next to 321 euro in carrier imposed fees.

Anyone that's has an idea what airline or stop is triggering these costs so that I can see if there is a workaround?