Arduino Knolleary PubSubClient将发布消息，但不能接收它们

I am using the Knolleary PubSubClient to make a connection to my MQTT server. I have been able to successfully authenticate and make a connection after not much work. I can even publish messages to topics. However, the issue I am having is that I can subscribe to topics and get no error, but when I publish to that topic (from mosquitto on my Mac) the callback does not get called and the message to the subscribe topic does not appear to be received. I have tried running a mosquitto subscription to the same topic at the same time, and that does receive the published message. Not sure if there is a problem in my callback code or what is going on here. Any help would be appreciated. Arduino code is below:I am using the Knolleary PubSubClient to make a