Central locking issues

[Alan Ald]

 

Hi guys 

can anyone help me? as I’m getting nowhere with the dealership. 
My 2017 XF has suddenly developed a problem with the central locking. 
If the car is left for an hour or more, it doesn’t respond to the key fob, have swapped the key fob with the spare but made no difference, open using mechanical key, alarm goes off until ignition button is pressed, then works fine ( locking and unlocking) until left for a hour, then no response again, any ideas?

It seems to have happened at the same time roadside assistance and app has run out of subscription.