Mycloud home duo cannot install with time machine

Hello, I’m new here. I installed a Mycloud home duo 16 TB on my network. It works and I can upload files via desktop app etc.
But, I don’t see the Mycloud to configure the backup via time machine on my mac.
What can I do.
I think, the afp protocoll must on the mycloud?
How can I install this?

Thanks for your answers.