They don't need to justify anything.
One very common practice people follow when they f*cked up in this part of the world is to keep asking you for things, a lot of them, with a lot of details, while they try to delay by bullsh*ting as much as possible.
They don't tell you from the begging all they need but they keep adding more on every email / correspondence. First they'd ask for say flight number, names and days. You reply promptly (hopping for the best) - they delay few days (they call it processing time) and then they ask for ticket number, flight hours, passenger DoB and maybe their shoe size, you reply promptly again and after few more dates (more processing time) they ask for receipt number, reservation number, date of booking, place of booking, how was the weather and whatever else they can thing of. Then suddenly they forget that they've got already your ticket number and ask again for it. All these in broken English and with very slow replying times. The process goes on and on until after maybe a month or more (if you haven't given up yet) they give you a ridiculous excuse claiming that according to their system everything is ok (whatever ok means to them). If you insist they say they will pass your case to their supervisor and the process starts over again until eventually you give up.
To be honest I haven't seen this from Garuda (which I don't fly often) but from other smaller companies (Nam air in particular) and internet booking sites (tiket.com) and in several other cases I've been through in small everyday matters.
The algorithm seems something like : BS, delay, repeat until customer gives up.
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