B-WL5M-SUBG1 Sigfox_AT_Slave Application LPUART has wrong pin configurations
As you can see below picture, B-WL5M-SUBG1 Connectivity Expansion Board's UART pins are PC0 and PC1:

But in the STM32Cube_FW_WL_V1.3.1 repository Sigfox_AT_Slave application for B-WL5M-SUBG1 describes uart pins are PA3 and PA2:

So in this case, application's UART AT interface doesn't work. Buf if you change LPUART1 pin configurations, it works fine:

Thank you for your interest.

