The Doorbell wont pair with my base station

[rekinneh]

connected doorbell to my system fine for about a week then within the space of 2 days i lost camera then audio phone end then no notification but worked ok woth chime. remove doorbell tried to reinstall but only got as far as doorbell syncing base station [blinking LED] but couldnt find it.I have looked at troubleshooting and thet suggest pressing reset button between batteries but i dont have one I have a switch with 1,2,3 on it but not sure what thats for. anyone help please

[jguerdat]

All of the audio doorbells have a reset/sync button between the batteries. It's small and the same color as the surroundings so can be hard to find but it's there.