diff --git a/.github/workflows/build_and_test.yml b/.github/workflows/build_and_test.yml
index 86eab8c2..e177985f 100644
--- a/.github/workflows/build_and_test.yml
+++ b/.github/workflows/build_and_test.yml
@@ -211,8 +211,8 @@ jobs:
     - name: Run tests with mpl test
       env:
         PYTKET_RUN_MPL_TESTS: 1
-        PYTKET_REMOTE_QUANTINUUM_USERNAME_QA: ${{ secrets.PYTKET_REMOTE_QUANTINUUM_USERNAME }}
-        PYTKET_REMOTE_QUANTINUUM_PASSWORD_QA: ${{ secrets.PYTKET_REMOTE_QUANTINUUM_USERNAME }}
+        PYTKET_REMOTE_QUANTINUUM_USERNAME_QA: ${{ secrets.PYTKET_REMOTE_QUANTINUUM_USERNAME_QA }}
+        PYTKET_REMOTE_QUANTINUUM_PASSWORD_QA: ${{ secrets.PYTKET_REMOTE_QUANTINUUM_PASSWORD_QA }}
       working-directory: ./tests
       run: |
         pytest --mpl-generate-path=integration/baseline
diff --git a/pytket/extensions/quantinuum/backends/quantinuum.py b/pytket/extensions/quantinuum/backends/quantinuum.py
index 4d09858a..33a0f309 100644
--- a/pytket/extensions/quantinuum/backends/quantinuum.py
+++ b/pytket/extensions/quantinuum/backends/quantinuum.py
@@ -326,6 +326,14 @@ def __init__(
         ] = dict()
 
         self._default_2q_gate = _default_2q_gate(device_name)
+
+        if self._default_2q_gate in self.two_qubit_gate_set:
+            pass
+        elif len(self.two_qubit_gate_set) > 0:
+            self._default_2q_gate = list(self.two_qubit_gate_set)[0]
+        else:
+            raise ValueError("The device is not supporting any two qubit gates")
+
         if compilation_config is None:
             self.compilation_config = QuantinuumBackendCompilationConfig(
                 allow_implicit_swaps=True, target_2qb_gate=self._default_2q_gate
diff --git a/tests/unit/api1_test.py b/tests/unit/api1_test.py
index aa71cdff..16feb96c 100644
--- a/tests/unit/api1_test.py
+++ b/tests/unit/api1_test.py
@@ -189,9 +189,13 @@ def test_custom_login_flow(
         ),
     )
 
+    qcc = QuantinuumConfigCredentialStorage()
+    qcc.save_user_name("user3")
+    qcc.save_refresh_token("token")
+
     backend_3 = QuantinuumBackend(
         device_name=fake_device,
-        api_handler=QuantinuumAPI(QuantinuumConfigCredentialStorage()),
+        api_handler=QuantinuumAPI(qcc),
     )
 
     circ = Circuit(2, name="default_login_flow_test").H(0).CX(0, 1).measure_all()
@@ -391,9 +395,8 @@ def test_device_family(
     )
 
     backend = QuantinuumBackend(
-        device_name=chosen_device,
+        device_name=chosen_device, api_handler=mock_quum_api_handler
     )
-    backend.api_handler = mock_quum_api_handler
 
     circ = Circuit(2, name="batching_test").H(0).CX(0, 1).measure_all()
     circ = backend.get_compiled_circuit(circ)
@@ -443,8 +446,8 @@ def test_resumed_batching(
 
     backend = QuantinuumBackend(
         device_name="H1-1E",
+        api_handler=mock_quum_api_handler,
     )
-    backend.api_handler = mock_quum_api_handler
 
     circ = Circuit(2, name="batching_test").H(0).CX(0, 1).measure_all()
     circ = backend.get_compiled_circuit(circ)
@@ -553,8 +556,8 @@ def test_submit_qasm_api(
 
     backend = QuantinuumBackend(
         device_name="H1-1SC",
+        api_handler=mock_quum_api_handler,
     )
-    backend.api_handler = mock_quum_api_handler
 
     qasm = """
     OPENQASM 2.0;
diff --git a/tests/unit/offline_backend_test.py b/tests/unit/offline_backend_test.py
index 7811616a..992cce07 100644
--- a/tests/unit/offline_backend_test.py
+++ b/tests/unit/offline_backend_test.py
@@ -151,8 +151,8 @@ def test_shots_bits_edgecases(n_shots, n_bits, language: Language) -> None:
 @pytest.mark.parametrize("device_name", pytest.ALL_DEVICE_NAMES)  # type: ignore
 def test_defaultapi_handler(device_name: str) -> None:
     """Test that the default API handler is used on backend construction."""
-    backend_1 = QuantinuumBackend(device_name)
-    backend_2 = QuantinuumBackend(device_name)
+    backend_1 = QuantinuumBackend(device_name, machine_debug=True)
+    backend_2 = QuantinuumBackend(device_name, machine_debug=True)
 
     assert backend_1.api_handler is backend_2.api_handler
 
@@ -163,8 +163,12 @@ def test_custom_api_handler(device_name: str) -> None:
     handler_1 = QuantinuumAPI()
     handler_2 = QuantinuumAPI()
 
-    backend_1 = QuantinuumBackend(device_name, api_handler=handler_1)
-    backend_2 = QuantinuumBackend(device_name, api_handler=handler_2)
+    backend_1 = QuantinuumBackend(
+        device_name, api_handler=handler_1, machine_debug=True
+    )
+    backend_2 = QuantinuumBackend(
+        device_name, api_handler=handler_2, machine_debug=True
+    )
 
     assert backend_1.api_handler is not backend_2.api_handler
     assert backend_1.api_handler._cred_store is not backend_2.api_handler._cred_store