State Bank Of India [SBI] — account hold lien created worth rs 1000000/- (rs ten lakhs)

Address:

Ranchi, Jharkhand, 834009

Dear sir/madam,
I had a sbi savings bank account at namkum branch ranchi jharkhand. On 15.3.18 i went to atm at about 9 pm to withdraw rs 2000/- out of rs 4541/- available balance but amount not disbursed due to reason "insufficient funds account withheld". I see sms in my mobile send at about 8.20 pm by bank then i shocked to see that a lien of rs 1000000/- ten lacs have been created in my account. I never taken any loan from bank or never stood as guarantee for any one. What is this can any one tell me.