SDI 12 compilation error

I am using the Mayfly logger board and trying to connect it to the wifi to communicate the data from the DF robot turbidity sensor with another board using the Wi-Fi Bee module with the example code provided with it. My issue is that whenever I compile, it says this: SDI12_ExtInts.h: No such file or directory. Putting the file in my Arduino/libraries folder creates many more errors, so I took it out. Please help troubleshoot this problem.

Link for the sample wifi code: https://github.com/EnviroDIY/ModularSensors/blob/master/examples/DRWI_Mayfly1_WiFi/DRWI_Mayfly1_WiFi.ino

Link for the turbidity sensor

https://www.dfrobot.com/product-1394.html

Arduino: 1.8.18 (Mac OS X), Board: “EnviroDIY Mayfly 1284p”

In file included from /Users/anishpatel/Documents/Arduino/libraries/src/sensors/MeterHydros21.h:73:0,
from /Users/anishpatel/Documents/Arduino/fdv/fdv.ino:159:
/Users/anishpatel/Documents/Arduino/libraries/src/sensors/SDI12Sensors.h:88:10: fatal error: SDI12_ExtInts.h: No such file or directory
#include <SDI12_ExtInts.h>
^~~~~~~~~~~~~~~~~
compilation terminated.
exit status 1
Error compiling for board EnviroDIY Mayfly 1284p.

This report would have more information with
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