Air India — poor services

Air india — my experience on services
This is with reference to my flight ai 780 from hyderabad to bhubaneswar schedule at 13.05 on 12th feb 2018. I reached at airport at 11.10 hrs. I had issued a check-in boarding pass at about 11.45 hrs and was told to wait at gate no. 26 to board the flight at 12.45 hrs. We (With my spouse) sat at gate no 26 waiting for boarding upto 12.55 hrs and seen there was no sign of boarding at gate no 26. When we asked there about our boarding, it was told that the flight boarding location is shifted to gate no. 101. As the time was short we rushed to gate no 101. But when we reached there, we saw the gate was allotted to indigo flight scheduled for bhubaneswar. We felt mislead. There was no announcement for the flight of indian airlines 780. From the display board it is known that the ai 780 flight boarding gate was changed to 23 and the gate was closed. While reaching at 13.10 at gate no 23, they denied us boarding. They told that they are helpless to help us. They had all efforts to reach me through phone but failed (As they told). We are totally distressed on missing the flight.
I noticed following shortfall in air india services
1. No adequate announcement for change of boarding gate.
2. No body bothered about non boarding of a passenger due to change of boarding gate. No grace timing was given for this change of boarding gate.
3. If someone missed boarding in time in other private airlines there is announcement frequently whereas air india failed to do so. Reason is well known (Private versus public sector) and that is why air india became less popular among airlines users