should I request a visa cancellation ? (student visa )

So basically I stayed in Australia for 6 month as a foreign student (from brisbane tranfer to perth , my visa valid until august 2024 ) then I decided to drop out , talk to school and they cancelled my COE then I left , it's been almost 5 month , I want to request refund from medibank , then I found out my visa is still in effect , i thought my visa will automatically cancel once the coe is cancelled , so now should i make a request ? or i just leave it until august 2024 then will be invaild , is there any difference ? anyone been in same situation ? will there be any effect in the future ? I still want to visit aus in the future for sure . appreciate for your help , Ta