Improvements were made to the behavior and messaging around this but that was through a software update in 2018. You most likely have a newer software version on the machine already. If you do not have a productivity kit that may help you. Here's a snippet from the productivity kit details .PDF that I think is relevant.
We have a VersaLibnk B405 that get a message on the front panel when copying that says,
"Please wait for existing jobs to complete and try again." when copying from the device.
Would a Productivity Kit or other option help alleviate this error? We are currently upgrading to the latest software. Any help would be appreciated.