diff --git a/src/cutecoin/core/graph.py b/src/cutecoin/core/graph.py
index a192d6d06bbbf5bfd9eb84cb2a5b604c5e2c05ae..1665d83fabcead7d9225a05d9033ecb9decb7ccc 100644
--- a/src/cutecoin/core/graph.py
+++ b/src/cutecoin/core/graph.py
@@ -90,11 +90,11 @@ class Graph(object):
             if node['id'] in tuple(done):
                 continue
             identity_selected = identity.from_handled_data(node['text'], node['id'], BlockchainState.VALIDATED)
-            certifier_list = identity_selected.certifiers_of(self.app.identities_registry, self.community)
+            certifier_list = identity_selected.unique_valid_certifiers_of(self.app.identities_registry, self.community)
             self.add_certifier_list(certifier_list, identity_selected, identity)
             if identity.pubkey in tuple(self._graph.keys()):
                 return False
-            certified_list = identity_selected.certified_by(self.app.identities_registry, self.community)
+            certified_list = identity_selected.unique_valid_certified_by(self.app.identities_registry, self.community)
             self.add_certified_list(certified_list, identity_selected, identity)
             if identity.pubkey in tuple(self._graph.keys()):
                 return False
diff --git a/src/cutecoin/core/net/api/bma/access.py b/src/cutecoin/core/net/api/bma/access.py
index 5c48b0fb5a19edb7a2ad972a4dfb5096340b114c..b77dd961edbedee64a2c42cc555f8a2caf71290f 100644
--- a/src/cutecoin/core/net/api/bma/access.py
+++ b/src/cutecoin/core/net/api/bma/access.py
@@ -1,5 +1,6 @@
 from PyQt5.QtCore import QObject, pyqtSlot
 from PyQt5.QtNetwork import QNetworkReply
+from . import wot
 from . import blockchain, ConnectionHandler
 from .....tools.exceptions import NoPeerAvailable
 from ..... import __version__
diff --git a/src/cutecoin/core/txhistory.py b/src/cutecoin/core/txhistory.py
index a268190bf66f68530d3bd4d4e2a62c35c6e0d189..24d993d083732f5ab41b451d584354360da01d9a 100644
--- a/src/cutecoin/core/txhistory.py
+++ b/src/cutecoin/core/txhistory.py
@@ -173,7 +173,7 @@ class TxHistory():
                   if tx.state in (Transfer.AWAITING, Transfer.VALIDATING)] +\
                  [ud['block_number'] for ud in self._dividends
                   if ud['state'] in (Transfer.AWAITING, Transfer.VALIDATING)] +\
-                 [self.latest_block]
+                 [max(0, self.latest_block - community.network.fork_window(community.members_pubkeys()))]
         parsed_block = min(set(blocks))
         logging.debug("Refresh from : {0} to {1}".format(self.latest_block, current_block['number']))
         dividends_data = qtbma.ud.History.null_value
diff --git a/src/cutecoin/gui/wot_tab.py b/src/cutecoin/gui/wot_tab.py
index 597c9904ee88fe0d768dacd6820d4c41e6f36981..744b5a34062d222b908c47475a025de9183e75a4 100644
--- a/src/cutecoin/gui/wot_tab.py
+++ b/src/cutecoin/gui/wot_tab.py
@@ -87,8 +87,8 @@ class WotTabWidget(QWidget, Ui_WotTabWidget):
             identity.inner_data_changed.connect(self.handle_identity_change)
 
         # create Identity from node metadata
-        certifier_list = identity.certifiers_of(self.app.identities_registry, self.community)
-        certified_list = identity.certified_by(self.app.identities_registry, self.community)
+        certifier_list = identity.unique_valid_certifiers_of(self.app.identities_registry, self.community)
+        certified_list = identity.unique_valid_certified_by(self.app.identities_registry, self.community)
 
         # create empty graph instance
         graph = Graph(self.app, self.community)