You are right in insisting for a Clearance Certificate from the bank. You should remain firm on this demand. As an initial step, suggest you write a letter in correct English to this branch of the bank stating the incident briefly and clearly, and demanding a Clearance Certificate. Take the original letter and a copy to the bank and ask the manager to receive the letter making him sign on the copy and putting the bank's seal. The bank's seal is very important. If he refuses, don't argue or fight him. Send the letter to the bank branch through courier service or registered mail and keep the courier dispatch receipt with you. Follow up with him couple of days after you are sure the bank has received your letter. I am almost sure they will give you your clearance letter. If they still don't, PM me and I may be able to guide you on the next step. But then that would be over a cup of tea and some biscuits!