How to remove excess ITC

Sohil Ansari (Student) (48 Points)

03 June 2018  
when we r filling 1st GSTR3B for July-17, in one of our clients GSTR3B by mistaken we took total sales amount in ITC, and at that time no options available for reset 3B, we filled as it is and still that credit available but we never used that credit,

i request to please suggest me what we can have to do for nullify that credit ?