Even though it generated 4,000 messages for vaccine recipients on the CoWIN app on Monday, the alerts did not reach most health workers and the BMC started calling people in the evening. The civic body had decided to go ahead with the vaccination drive on Tuesday irrespective of how the app worked and had been verifying with war rooms at ward-level throughout the evening if the alerts were getting delivered. While on Friday, ahead of the first day of the drive, messages could not be generated, on Monday they did not get delivered.

The civic body started contacting shortlisted recipients via the war rooms.