[Backend] Fix null pointer exception in Asset Issuer

[emdevelopa]

Description
This task involves system optimization for the Asset Issuer module.
The goal is to fix null pointer exception in Asset Issuer to enhance the platform's robustness, security, and developer experience.

Requirements and context

• Must be secure, tested, and documented
• Adhere to the Drips Wave design and engineering standards
• Ensure full test coverage for new logic
• Specifically focused on backend system optimization and security integrity

Suggested execution

Fork the repo and create a branch
git checkout -b feature/be-fix-null-pointer-exception-in-asset-issuer
Implement changes

Review existing implementation in Asset Issuer
Apply changes: Fix null pointer exception in Asset Issuer
Ensure robust error handling and logging
Test and commit

Run unit and integration tests for Asset Issuer
Cover edge cases and validate security assumptions
Include test output and security notes in the PR
Example commit message
feat(backend): fix null pointer exception in Asset Issuer

Guidelines

Complexity: High (200 points)
Assignment required before starting
PR description must include: Closes #[issue_id]