How can I create space without resetting? I have only WhatsApp installed in the phone memory. How did the system file expand so much? On my computer it shows 2.85 GB of system files. But on my phone it shows 6.65 GB.
Which phone and which OS?
If you go to storage check, what do you see occupying space? Especially under temporary data and apps. If your apps are using a lot of space, reinstall them to get rid of excess data.
For example, on whatsapp, you could backup your chat history, uninstall whatsapp and then reinstall. That way you'll recover some space
If you have used hyperlapse, remove that and reinstall
Check under instagram beta, it saves every image you upload