diff --git a/monitor/mocks/mqtt_monitor.go b/monitor/mocks/mqtt_monitor.go
index bbc8e7c..a08e814 100644
--- a/monitor/mocks/mqtt_monitor.go
+++ b/monitor/mocks/mqtt_monitor.go
@@ -10,7 +10,7 @@ type MockMQTTMonitorClientI struct {
 }
 
 // AddParticipant mocks base method.
-func (m *MockMQTTMonitorClientI) AddParticipant(address string, lastSeenTS int64) error {
+func (m *MockMQTTMonitorClientI) AddParticipant(address string, _ int64) error {
 	m.myStringList = append(m.myStringList, address)
 
 	return nil
@@ -28,8 +28,7 @@ func (m *MockMQTTMonitorClientI) SelectPoPParticipantsOutOfActiveActors() (strin
 }
 
 // SetContext mocks base method.
-func (m *MockMQTTMonitorClientI) SetContext(ctx types.Context) {
-	return
+func (m *MockMQTTMonitorClientI) SetContext(_ types.Context) {
 }
 
 // Start mocks base method.
diff --git a/tests/e2e/dao/pop/selection_suite.go b/tests/e2e/dao/pop/selection_suite.go
index d6fb23d..3a1b25a 100644
--- a/tests/e2e/dao/pop/selection_suite.go
+++ b/tests/e2e/dao/pop/selection_suite.go
@@ -165,7 +165,8 @@ func (s *SelectionE2ETestSuite) TestPopSelectionNoActors() {
 
 func (s *SelectionE2ETestSuite) TestPopSelectionOneActors() {
 	err := e2etestutil.AttestMachine(s.network, machines[0].name, machines[0].mnemonic, 0, s.feeDenom)
-	monitor.MqttMonitorInstance.AddParticipant(machines[0].address, time.Now().Unix())
+	s.Require().NoError(err)
+	err = monitor.MqttMonitorInstance.AddParticipant(machines[0].address, time.Now().Unix())
 	s.Require().NoError(err)
 
 	out := s.perpareLocalTest()
@@ -176,7 +177,8 @@ func (s *SelectionE2ETestSuite) TestPopSelectionOneActors() {
 
 func (s *SelectionE2ETestSuite) TestPopSelectionTwoActors() {
 	err := e2etestutil.AttestMachine(s.network, machines[1].name, machines[1].mnemonic, 1, s.feeDenom)
-	monitor.MqttMonitorInstance.AddParticipant(machines[1].address, time.Now().Unix())
+	s.Require().NoError(err)
+	err = monitor.MqttMonitorInstance.AddParticipant(machines[1].address, time.Now().Unix())
 	s.Require().NoError(err)
 
 	out := s.perpareLocalTest()