Can you send me the contents of this file after reproducing this?
C:\ProgramData\Mount and Blade II Bannerlord\logs\rgl_log_xxxxx.txt
Please note that ProgramData folder is a hidden one.
Can you also try reinstalling the BattlEye?
Under the games installation folder please navigate to this folder:
"...\Mount & Blade II Bannerlord\bin\Win64_Shipping_Client\BattlEye"
First, run the uninstall.bat file and install.bat afterwards. Please make sure that your game is not running in the background.