I have a transit that will pass by CGK airport on 25 Jan 2021

Airlines sell tickets through multiple channels (both online and offline), and they are not required to verify each passenger's eligibility for entry or transit.

Moreover, it's impossible to reliably check entry requirements for each individual passenger automatically. For instance, had you been an Indonesian citizen or resident with the same ticket, perhaps you would have been allowed to transit. Even check-in agents can get this task wrong and occasionally need to ask superiors or wrongly refuse people.

If there is a warning on the website, it's usually generic, along the lines of "the passenger is responsible to comply with any entry or transit requirements".

Your best bet is to ask the airline to reschedule your flight or rebook you on a different itinerary. One time, British Airways rebooked me for free when my ineligibility to transfer was discovered upon check-in. However, this is a courtesy, not an obligation, so make sure to ask nicely.

As far as I'm aware, the only airline currently flying non-stop from Jakarta to Sydney is Garuda. If Garuda is really not permitting transit through CGK, your itinerary appears to be impossible.

If Turkish Airways has sold you this as a single itinerary, they are responsible for getting you to Sydney, so I suggest you reach out and ask them for alternatives. Flight capacity to Australia is extremely limited right now though.

Checking with Garuda would also not hurt, maybe they have an exception worked out for Turkish or something. They won't be able to help with rerouting though.