Hi @Vy,
Thanks for the detailed description.
This is a very uncommon problem, perhaps something is wrong with your OneDrive.
However, we can work together to narrow down and resolve the situation. So, please kindly provide more information below to let us work further.
1.Make sure again that you are not using the same account for OneDrive on device A and device B. You can go to OneDrive settings to check.
2.Please open settings->Apps->Advanced app settings. Make sure "Share across devices" is off.
3.Try deleting the OneDrive credentials and then restart OneDrive.
4.If the problem persists, then please sign into OneDrive on a device other than A and B to see if the problem reappears on other devices as well.
If the answer is helpful, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".
Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.