Unable to run Gas Sensor V2(Multichannel) on a oumex 32v4 board


I preheated the sensor for 24 hours and then ran the code from the example folder in the grove library and nothing appeared on the serial monitor. The link to the library is here: Grove - Gas Sensor V2(Multichannel) | Seeed Studio Wiki . I am very new so I may have done something wrong. if I have please let me know or I think the sensor is broken. I did not purchase the screen which they used in the tutorial however, in the examples library there is no use of a display in the code.

Also, when i have multiple of the sensors connected to the base shield, the numbers i get is odd or they don't work at all. One thing it could be is that on the oumex 32v4 board the there are two extra pins on the shield that are not being used. a 5v and one that I am not sure what it is. I can send a link if you need

Thanks a lot!