Could not Compile the code

[apsathyan]

Hello All,
When compiling i am getting this error message.
c:/users/sathya/appdata/local/arduino15/packages/esp8266/tools/xtensa-lx106-elf-gcc/2.5.0-4-b40a506/bin/../lib/gcc/xtensa-lx106-elf/4.8.2/../../../../xtensa-lx106-elf/bin/ld.exe: sketch\wemos_Hall_13.7.20.ino.cpp.o: in function connectWifi()': C:\Users\Sathya\Downloads\arduino-esp8266-alexa-multiple-wemo-switch-master (2)\arduino-esp8266-alexa-multiple-wemo-switch-master\wemos_Hall_13.7.20/wemos_Hall_13.7.20.ino:165: undefined reference to BulbOn()'
collect2.exe: error: ld returned 1 exit status
exit status 1
Error compiling for board LOLIN(WEMOS) D1 R2 & mini.