Hi @myoui_hirota.
The D8 pin used by the " A B C D " column is actually the GPIO15.
This GPIO15 on Wemos Mini has a 10KOhm resistor for Gnd.
This affects the scanning done by the Keypad.h library.
Change the connection from D8 (GPIO15) to DO(GPIO16) and you will see that it works correctly.
RV mineirin
