Indian Overseas Bank — Denial of access to my locker and lack of response from branch

Being a NRI customer with IOB along with Locker holding, I wanted to have my spouse access my locker without my presence as I am not able to travel. The branch neither responds to the calls to bank/ to the emails to branch manager. After lot of complaints and escalation, they turn up responded with instructions and that was misleading and again they denied my locker access in spite we travel in person. Negligence and denial of my possession is the severe complaint against them and I have all proper communication and evidences for this issue. Kindly assist me in taking a legal action.