Hi @zeynepilke,
Check if you could see the setup log to get more details.
Path: %programfiles%\Microsoft SQL Server*nnn\Setup Bootstrap\Log*
In addition, here is a similar thread which has the same issue you may take a reference to.
As per my understanding,this issue arises when setup files are not downloaded completely.. You may have to download entire setup first and install it later as shown in screenshot below
Regards,
Zoe Hui
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