Bro see , the magnetic field of outer loop is outwards at centre and it will exert a torque on smaller loop , And vice versa. ( same the smaller loop do , I.e .. rotate outer loop)
If you find initial torque using mB it will be greater for outer loop , which makes it complicated
@Satyendra_Srivastva assume current in same direction as it is not mentioned
The torque is function of theta which is different for both as the magnetic moment vectors and fields are shifting.
So try to imagine at some general angle theta and figger out, last time I used m b= i alpha to figger out relationship between the angles of both , but it didn't work