Read function in MQTT says " There are no messages waiting to be read."

I am creating an app on MATLAB that publishes and subscribes data to a MQTT broker. Publishing data works fine but when i subscribe and read the data, it says "There are no messages waiting to be read." but the topic has messages. i am using MQTT box client to test this and i have a different subscriber setup as well. The second subscriber gets the messages but MATLAB shows an error saying there are no messages

image from the second subscriber showing there are messages