Cash deposit in saving bank account generated through business and business entity is also having current account

sir,
assessee has made cash deposit in his saving bank account stating that cash was generated through business run by one of the family member. As the cash handling charges in the current account of business is too high and to avoid such charges, assessee is depositing cash generated from business entity into his saving bank account. Assessee has also submitted that the funds were transferred to current account of the business entity within a span of 1 or 2 days. AO has made addition U/sec. 68 on the ground that the amount is unexplained cash credit and to be added U/sec. 68, even though assessee has given complete details/documents of the persons from whom cash is received. Whether addition u/s 68 is justifiable ?