【请教】请问有大佬知道这个问题该怎么解决吗？

Arduino:1.8.13 (Windows 10), 开发板："NodeMCU 1.0 (ESP-12E Module), 80 MHz, Flash, Legacy (new can return nullptr), All SSL ciphers (most compatible), 4MB (FS:2MB OTA:~1019KB), 2, v2 Lower Memory, Disabled, None, Only Sketch, 115200"
c:/users/86182/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\Esp8266_Clock_Weather.ino.cpp.o: in function `drawForecastDetails(OLEDDisplay*, int, int, int)':
C:\Users\86182\Pictures\chuangxinshijian\http+mqtt_test\Esp8266_Clock_Weather/Esp8266_Clock_Weather.ino:341: undefined reference to `subscribeTopic()'
c:/users/86182/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\Esp8266_Clock_Weather.ino.cpp.o: in function `connectMQTTserver()':
C:\Users\86182\Pictures\chuangxinshijian\http+mqtt_test\Esp8266_Clock_Weather/Esp8266_Clock_Weather.ino:370: undefined reference to `subscribeTopic()'
c:/users/86182/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\Esp8266_Clock_Weather.ino.cpp.o: in function `wificonnect()':
C:\Users\86182\Pictures\chuangxinshijian\http+mqtt_test\Esp8266_Clock_Weather/Esp8266_Clock_Weather.ino:233: undefined reference to `receiveCallback(char*, unsigned char*, unsigned int)'
collect2.exe: error: ld returned 1 exit status
exit status 1
为开发板 NodeMCU 1.0 (ESP-12E Module) 编译时出错。
在文件 -> 首选项开启
“编译过程中显示详细输出”选项
这份报告会包含更多信息。