Problems in disconnected situations due to distance during update

[VUNO-wonwoohan]

During the update process, we intentionally widened the distance and created an update not possible situation.
The message "Disconnecting..." remains on the top of the cell phone and appears to be waiting indefinitely.
At this time, when you exit the app, it ends together.
NordicDFU seems to fall into an infinite loop while disconnecting from a Bluetooth device, is there a solution?
I used the latest version of 6.0.1.