@mungi sai meghavardhan I'm sorry to hear about the situation with your PostgreSQL server.
Please let me know if your issue resolved? so we can guide you further on this.
To retrieve your lost data, you can perform a point-in-time restore to create a copy of your server to a known good point in time within the backup retention period you have configured for your server.
https://learn.microsoft.com/en-us/azure/postgresql/flexible-server/concepts-backup-restore
Regards
Geetha