Alliance Air is Refund of Cancelled flight

We booked a returned ticket of Aizawl to Shillong on 06/06/22 and scheduled to return on 9/9/22.

We reached Shillong Airport on 09/06/22 as per schedule only to be informed that Flight is cancelled due to technical reason. When I asked why we were not informed about that, the station manager said that they informed every passengers and showed me some call he stated to have received regarding flight cancel.