Wrist based HRM Turns Status off randomly

Its happened a few times now but just happened after i completed a bike ride. Got back uploaded data to Garmin Connect. Did nothing else and realised I was not getting any Heart Rate info. Checked it was on but had turned itself off. Has  happened before quite randomly. Anybody else had same problems? Is there any updates I should think about

Running software version 11.00

ANT/BLE/BT 4.30

Sensor Hub 2.40