Can't get the Pourbaix diagram package to work

Hi ! I am new with the Materials Project and pymatgen. I am trying to use the Pourbaix diagram package to work. My goal is to be able to plot some 3 elements diagrams. However I cannot figure out how to plot the pourbaix diagram for Cu. I found some exemples but I always get the same error (see screenshot attached)
What should I do ?

Make sure you have the latest version of mpcontribs-client installed

Thanks, it was indeed the issue.