As you want here giving below North Malabar Gramin Bank (Kerala Gramin Bank) Trivandrum branch contact address on your demand :

Address
North Malabar Gramin Bank (Kerala Gramin Bank) Trivandrum
Trivandrum Vizhinjam Rd, Manacaud, Thiruvananthapuram, Kerala 695023
Phone: 0471 246 5699

Hours:
Wednesday 10AM–3:30PM
Thursday 10AM–3:30PM
Friday 10AM–3:30PM
Saturday 10AM–3:30PM
Sunday Closed
Monday 10AM–3:30PM
Tuesday 10AM–3:30PM

For more info of Kerala Gramin Bank (North Malabar Gramin Bank) Branches here I am telling process

Go to the Kerala Gramin Bank official website

Click on find branches option which given on the top right side

By click there you will land on branch locator page which look like given below image