Service of trustee process on a financial institution authorized to do business in this State or credit union authorized to do business in this State, as defined in Title 9-B, section 131, is effected by one of the following means:
1. Designated office. Personal service by any lawful means upon the office designated by the financial institution or credit union for service of trustee process in a registry maintained for this purpose by the Secretary of State; or
2. Acceptance by designated officer or employee. Acceptance of service in writing by an officer or employee of the financial institution or credit union expressly authorized to accept service of trustee process.