Trend Micro is currently investigating this concern and are waiting for updates from Apple. Current workaround is to restart the machine after completing the upgrade to macOS 11.3 or 11.3.1. All agent features are seen to work after performing this.
For users of macOS Big Sur 1.4, refer to this KB article:
Trend Micro Apex One (Mac) and Worry Free Security Agent for MAC compatibility with macOS Big Sur 11.4
For more information about the compatibility and release dates, refer to Matrix of supported macOS and support dates for Trend Micro Apex One (Mac).
In case further assistance is needed, please contact Trend Micro Technical Support.