alarm appears disabled but dont know how to re-enable
Enabling/Disabling need proper permission (by default the Operator Configure permission).
The workplace you took the picture from lack permission to enable.
Log over to an admin and try again, or right click the object, select Details... then Permissions, mark Operator Configure, then click Explain... and you will be presented with a map from where the deny originates (or if not allowed anywhere, deny will be implicit).
Only "power operators" should have permission to disable. Alarm Lists can be filtered to not display disabled alarms which can lead to very nasty situations when the operator believes there is no alarm while in fact it has been suppressed (and filtered) from his view.
Read more about configuring security in the user's guides.