I turn on my HTC VIVE Flow and a Unity loading icon appears. Then it shows me an error message 'Error not enough Storage space to install required resources'. And hard resetting doesn't help.

[HanSaj]

The option to access the internal files via USB debugging mode does not appear as the VR headset doesn't even look properly booted when the error message appears.

Prior to the error, I think I tried a phone mirroring application. And then this appeared. Rendering the VR headset useless now for any operations.