A Microsoft file hosting and synchronization service.
Hi. I'm Brian and I'll try to help.
If your subscription expires and your quota reduces from the 1TB amount to the 5GB, files on your computer should still be available. Nothing should happen to them. You just won't be able to create anything more in the OneDrive folder tree, which usually includes the Desktop, Documents and Pictures folders. Moreover, you have about 30 days to save the data from OneDrive to another location on your computer. After that and for a period of time I can't seem to find proper documentation on, the files become read-only so you can download it. After that, the data becomes inaccessible but If you renew the subscription within the following six months, you should get access back. After six months, the data is permanently deleted but I can't find any documentation on which part of the over quota data gets deleted. I don't know if it's by oldest, newest or largest. See https://learn.microsoft.com/microsoft-365/commerce/subscriptions/what-if-my-subscription-expires.
Is this a personal subscription or an educational subscription?