Baffled

2014 Note automatic, have had trouble unlocking the car using the button on the door with the keyless fob in my pocket so have used the control on the fob instead. Assumed the battety in the fob needed replacing, used a new duracell battery. Now when I try to unlock the car using the key fob, the button on the door handle still won't work, the alarm starts. Any ideas what's wrong? Haven't used the car for 2 weeks due to lockdown.