Key problem

[ARDR]

Afternoon 

just encountered a problem 

I went out today, about 4 miles from home car  opened up ok, started and drove fine. Parked and locked the car. Went away for half an hour. Returned to car and key fob was dead. Could not get into car. Remembered that you could pop the cover beside door handle to use metal key. Did that, got in but could not start the car as it is a button start /stop. 
is there a hidden key slot to use the key to start the car? Can’t find anything g in hand book. So if keyless entry and start button and your key fails. You can get in car but can’t start it? Is this right? Any knowledge out there…. 
No warnings given anywhere that battery was failing either! 

[arnold]

I seem to remember you hold the key near the start stop button then press it. Mine did the same but my kessy car key was faulty full stop. I got a quote from the main dealer 380 to replace and recode but managed to find a reliable chap to repair it for 40 quid.