Starting a new plan re-use the previous backup history Here is the response from the support and I can confirm that their action plan resolved my issue:
Hello Nicolas,
Thank you for contacting us.
It is not a bug. The backup is performed according to the local database, containing all the records of the files uploaded. It was not updated, which resulted in this behavior.
Please synchronize the repository following these steps:
1. Go to Settings - Application - Synchronize Repository.
2. Choose your account from drop-down menu.
3. Press Synchronize Now
Please let us know if it helps.
Thank you