In case of an address conflict, pulling/plugging the ethernet cable does not make the device using its IP address again (BOOTP/DHCP only)

In case of an address conflict, pulling/plugging the ethernet cable does not make the device starting the DHCP/BOOTP state machine again.
The network status LED is of and the module status LED is flashing green. So it seems like the conflict has been clear internally, but no IP address is obtianed from the DHCP/BOOTP server.