Indigo Airlines — Cancellation of flight without any sms, Changing the flight non stop to 1 stop, seat selected not available in change flight

Indigo is doing malpractice with customer booking. they are cancelling flight without giving any sms to customer. they are changing flight automatically. changing flight nonstop to 1 stop. if we ask for the same flight in next day they are telling it is not available but in website it is showing available.