Dashboard shows wrong capacity value, double present

I have the My Cloud 3TB with the latest FW installed,
the capacity in my dashboard shows double, a capacity of 6TB.
In my pc under network locations everything is displayed correctly.
Anyone have an idea ?
Restarting the cloud does not help.

Do you have a USB hard drive attached to the My Cloud?

If so, when one enables the option USB Content Availability in the Dashboard > Settings > General > Cloud Access, the capacity of the USB hard drive will be included into the Capacity chart values. Disable this option and the Capacity chart values should return to showing only the internal single bay My Cloud hard drive values.

Thank you for your quick response.
This solves the problem.
I had indeed attached a MyBook 3TB via USB.
Many thanks for this.