How to solve unrecognized function or variable in Matlab

Hi Team

 

I have this error on my Matlab and cant seem to solve it. "Unrecognised function or variable 'avg_temperature'. My code is below and i am following this link to create an email alert to my channel;

 

https://www.mathworks.com/help/thingspeak/sendalert.html

data = thingSpeakRead(929272, "NumMinutes", 100);

aveTemp = mean(data(:,3));

apiKey = 'O6P4N8AVZWKNGK5U';

alertURL = "https://api.thingspeak.com/alerts/send";

options = weboptions("HeaderFields",["ThingSpeak-Alerts-API-Key", apiKey]);

alertBody = sprintf("The temperature is %0.2fF.", aveTemp);

alertSubject = sprintf("! Temperature exceeded 60.0F!");

if avg_temperature > 60.0 webwrite(alertURL, "body", alertBody, "subject", alertSubject, options);

end