United Bank Of India [UBI] — Amount debited unknowingly

Address:

Kasaragod, Kerala, 671121

Account number *
Transaction date 25/05/2017
Transaction amount inr 457.12
Transaction type dr
Transaction description nach/bdach-ilfsb/citi[protected]

Everymonth there is some amount dr. From my account was started from january 2017.
How i can come to know there are any unknown 3rd party's debuting my account.
The discripion is showing nach/bdach-ilfsb/citi[protected]
Please help me...