[#172539318] Improved 'invalid JSON' error message, added 'use' statements
[#172539318] Improved 'invalid JSON' error message, added 'use' statements

subscribepro/subscribepro-magento2-ext,subscribepro/subscribepro-magento2-ext,subscribepro/subscribepro-magento2-ext,subscribepro/subscribepro-magento2-ext