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The log file says that OneDrive itself throws an error we try to upload the file. Based on their GitHub issues, this is a recurring issue for some file names. They fix it and it happens again with some different file names. I'm not Microsoft so I can't know what really happens. I suspect that maybe the random string at the end of the backup archive's name may be triggering a bug in the OneDrive service itself. We can try to work around that. Here's how.

Create a new folder on your site called backup_vault. Make sure it's writeable by PHP.

Edit your Akeeba Backup backup profile's Configuration. Set the output directory to the backup_vault directory you created (you might need to use the folder browser to locate it).

Set the Backup Archive Name to site-[HOST]-[DATE]-[TIME_TZ]

Save & Close the Configuration page.

This should change the file names of the generated backup archives to something I would hope wouldn't trigger an internal bug in the OneDrive service itself.

If the problem persists maybe you should consider using a more reliable file storage service. I've had a lot of issues as a user of consumer-grade file storage services such as Dropbox, OneDrive, Google Drive and pCloud (yeah, I've been through all of them). Even when storing my own files, using their official client software (NOT Akeeba Backup) I've run into issues with files not uploading, conflicting files appearing when they shouldn't, filenames getting mangled because they contained a valid character (e.g. Greek) they didn't really test with and so on. In the end of the day, only enterprise grade file storage such as Amazon S3, Microsoft Azure BLOB Storage, OpenStack Swift (RackSpace CloudFiles, OVH, etc) and BackBlaze B2 seem to be reliable enough to trust them with my important data such as backups.