Failed to execute MI command - STM32L151V8T6A

I am working with CubeIDE 1.4.0 on Windows 10 and using STM32L151V8T6A on my prototype board.

However not able to fix the errors below.

Would be of great help to get to know and fix the cause

Thanks a lot

Error message from debugger back end:

Error finishing flash operation

Failed to execute MI command:

load C:\\Robertshaw\\Projects\\WHC_BB01\\Debug\\WHC_BB01.elf 

Memory Programming ...

Opening and parsing file: ST-LINK_GDB_server_a10532.srec

 File     : ST-LINK_GDB_server_a10532.srec

 Size     : 7164 Bytes

 Address    : 0x08000000 

Erasing memory corresponding to segment 0:

Error: Flash loader cannot be loaded

Error: failed to erase memory

Encountered Error when opening C:\ST\STM32CubeIDE_1.4.0\STM32CubeIDE\plugins\com.st.stm32cube.ide.mcu.externaltools.cubeprogrammer.win32_1.4.0.202007081208\tools\bin\STM32_Programmer_CLI.exe

Error in STM32CubeProgrammer

Debugger connection lost.

Shutting down...