diff --git a/core/group_party.go b/core/group_party.go
index 0b0da18..0b76298 100644
--- a/core/group_party.go
+++ b/core/group_party.go
@@ -635,7 +635,8 @@ func (gp *groupParty) updateMemberDocument(gid groupID, mid accountID, doc bson.
 		id: gid,
 		rh: gp.rh,
 	}
-	prefixPath := fmt.Sprintf("$._members.%s.", gd.tid(mid))
+	prefixPath := fmt.Sprintf("$._members.%s._body.", gd.tid(mid))
+
 	err := gp.rh.JSONMSetRel(gd.strid(), prefixPath, doc)
 	if err != nil {
 		return err