Bank customer needs help

I opened a bank account with Bank of Tonga sometime in the 1980s before I emigrated to the United States of America in 1986. I left my bank transaction booklet (tohi pangike) with my mother so she can conduct all my banking activities for me. Bank of Tonga eventually changed its name to Wespac Bank of Tonga which is the current management. Unfortunately, my mother misplaced the booklet along with the account number and she can no longer make any deposits to the account. WBT started a policy which allow them to charge a large amount of penalties to any account that is not active. - ‘Aisea T. Tu‘ikolovatu