It seems it is known issue and finally I encountered it as well. (2.5Gb of real storage used while it says 10Gb)
At the same time could you please provide some solution for client side (any script to execute or at least to ignore error code or other programming hack) because I have a strong feeling that the issue will apear again very soon since I am using automated cloud syncronisation (rclone). I am using actually my own shell scripts and oauth to interact with box storage. Thank you.