State Bank Of India [SBI] — deduction of 147.50rs in my sbi account

Address:

Mandya, Karnataka, 571401

On 28th of feb 2018 sbi has deducted 147.50 rs from my account without any reasons, the message they sent for deduction is as followed

"your a/c xxxxx495382 has a debit by transfer of rs 147.50 on 25/02/18. Avl bal rs 1, 260.19. Download yono @ www.yonosbi.com"

I want know the reason for sbi's blunder. I haven't done any transaction on that day. They want us (Non working class - students) to maintain a min balance of 2000rs and we r when we are trying hard for it, they do this.