Before you proceed, you need Spaces installed on your phone.
By default, the members cannot see each others' contact details. However, the members can control the information seen by others.
I can see the contact details of some members, why is that?
If the contact detail is already saved in your phone and the same member is added to Space, you will be able to see the contact details.
If you want to completely hide the details with no one be able to see, please follow this guide, click here.
You are done!