[fix] fix null in written_on identity field

src/sakia/services/identities.py

@@ -116,8 +116,8 @@ class IdentitiesService(QObject):
                     self.currency, blockstamp.number
                 )
                 identity.membership_buid = blockstamp
-                identity.membership_type = ms["membership"]
-                identity.membership_written_on = ms["written"]
+                identity.membership_type = membership_data["membership"]
+                identity.membership_written_on = membership_data["written"]
                 identity = await self.load_requirements(identity)
             # We save connections pubkeys
             identity.written = True