STM32WB5MMGHx custom app couldn't go back to OTA Loader App

[Jtron.11]

I am following this video link showing step by step to create OTA app.

https://www.youtube.com/watch?v=mRzZOa3jmuM.

I am successfully to create the custom application, download the OTA loader app at 0x08000000, and the custom's app at 0x08007000. The problem I am facing is whenever I sent some data to OTA Reboot characteristic, the custom app is just reset, then go back to the custom app. It didn't enter the OTA loader app. Am I missing something like the erase current app function? I also notice in my custom app, once the ST BLE tool box or ST BLE Sensor app connects to my device, it didn't show the OTA reboot option like when I tried the BLE_p2pServer_ota.

[ALABR.1]

Let's said you have generated the following for your custom service:

F000AAAA-0452-4000-C000-000000000000.

Then for your 2 char you may change to:

F000BBBB-0452-4000-C000-000000000000 #CharA

F000CCCC-0452-4000-C000-000000000000 #CharB

Only the bits[16:32] change. Can you try this ?