Member profile URL now has "member-2", not "member"

When we installed Membership 2 Pro on one of our new WP/BuddyPress sites, all the member URLs are now in the format: http://oursitename/members-2/username.

Having "member-2" as part of the URL is not acceptable. Even when we deactivated the Membership 2 Pro plugin, or rolled back to a version before the plugin was installed, this new "member-2" designation is still there in all the member URLs.

How do we revert to the standard "member" in the URL?