2014 S60T5, intermittent no - lock

[azureblue]

2014 V60 T5:
1 - get into unlocked car
2 - Start car
3- Go somewhere
4 - Try to use fob to lock car, but it doesn't work. Open and shut all doors, no luck.
5 - Fine. Leave car unlocked. Come back in about 15 minutes and the fob locks and unlocks the car.
6 - Once the lock system works, it will continue to work for the trip...
Same pattern 3 times..
And I checked the fob's 2 batteries and the connectors inside the case.... I carry it in my my pocket, BTW..
Ideas?