West Bengal bans app-cab aggregators from using private (non-transport) vehicles; platforms must remove them in 7 days and maintain state offices for compliance. Kolkata: The Bengal government has prohibited On Demand Transportation Technology Aggregators (ODTTAs) from engaging non-transport category vehicles for commercial services through. West Bengal orders app-cab aggregators to remove private vehicles without commercial licences within seven days and set up a local office for grievances.