WiFi sleep problem

[dogbreath]

Using an V-LINK OBD2 WiFi transmitter with a first generation iPad running Dashcommand to monitor fuel efficiency on a 2008 Smart fourtwo cabrio. The dongle is supposed to have a sleep mode, but this unit will not reconnect after the car has been shut down for several hours; have to disconnect and reconnect to re-boot it. Has anyone had a similar issue and were you able to make adjustment to get sleep mode to function properly.