Working with Multisite and UM

Hello,

Im building a network of multisites and using Ultimate member as the members directory plugin.
I was trying to create an invitation only registration but something just doesnt work…
Im not able to see the place where the invitation code should be inserted on both the default and the UM registration pages.

Can this plugin work on Multisite? If yes, how can i show the line of where the invitation code should be inserted?

Thanks!

p.s. Ive clicked “show the code request on the wp registration page” nothing changes.

The page I need help with: [log in to see the link]