We really appreciate that you bring your concern here.
Make sure that you did all the steps below:
To use the Uninstall Protection feature of Mobile Security, follow the steps below:
1. Open the Trend Micro App. 2. Tap on Lost Device Protection. 3. Type your Trend Micro Password. On the next windows you will see Activate Device Administrator. 4. Tap on Activate. The next screen tells you that this setting will Erase all data. However, it can only do so if you manually choose to wipe data from the Lost Device Protection web portal. No data will be erased without your action. 5. Tap on Activate this device administrator.
After these steps the Uninstall Protection should be enabled.
If it is still not. please give us the model of your phone.