Your Microsoft storage is almost full

I received an email from *******@notificationmail.microsoft.com

saying my OneDrive account is full "Your email Microsoft storage is almost full. If your storage is full, you can’t back up, sync edits, or add files and photos to OneDrive, and you won’t be able to send or receive emails from your Outlook/Microsoft email accounts.

To avoid interruption, remove files in OneDrive, delete emails with large attachments in Outlook, or upgrade your storage". Unfortunately, I didn't realize it was probably a phishing scam, as I don't even use OneDrive and when I logged into my microsoft account later, I saw that One Drive was completely empty. I clicked the "Get a confirmation code" button and entered the code which came to me by email

Then I was offered to save the access key through Google, but I declined and got a message saying "error: access key not created" or something like that. Then I realized something was wrong and went to the official page to access my account. My One Drive account wasn't filled in there.

I suppose my Microsoft account may have been compromised via a phishing attack using a device code (OAuth). I entered a code that I thought was an OTP, but I am concerned it may have granted unauthorized access to my account. I have access to my account now, but I want to:

Revoke any unauthorized OAuth tokens or app access

Ensure my account is fully secure Could you please guide me on how to do this safely? Thank you.