Aggregation not working for EX3400

Hi guys, I have an unusual issue. I am configuring link aggregation on my EX3400 for the first time. I am experiecing the following issue. Can someone please have a look and tell me what am I missing? Thanks

Following is the configuration with the error message at the end.

SW_Lab# show interfaces ge-0/0/46
description "BACKUP ae0";
ether-options {
    802.3ad ae0;
}

SW_Lab# show interfaces ge-0/0/47
description "BACKUP ae0";
ether-options {
    802.3ad ae0;
}

{master:0}[edit]
SW_Lab# show interfaces ae0
description BACKUP;
aggregated-ether-options {
    minimum-links 1;
    link-speed 1g;
    lacp {
        active;
        periodic fast;
    }
}
unit 0 {
    family ethernet-switching {
        interface-mode trunk;
        vlan {
            members 100;
        }
    }
}

{master:0}[edit]
SW_Lab# commit check
[edit]
  'unit 0'
     logical unit is not allowed on aggregated links
error: configuration check-out failed