diff --git a/qiskit_dynamics/arraylias/register_functions/asarray.py b/qiskit_dynamics/arraylias/register_functions/asarray.py
index a4db54228..62c5d325b 100644
--- a/qiskit_dynamics/arraylias/register_functions/asarray.py
+++ b/qiskit_dynamics/arraylias/register_functions/asarray.py
@@ -27,6 +27,10 @@ def register_asarray(alias):
     def _(arr):
         return np.asarray(arr)
 
+    @alias.register_fallback(path="asarray")
+    def _(arr):
+        return np.asarray(arr)
+
     @alias.register_function(lib="scipy_sparse", path="asarray")
     def _(arr):
         if issparse(arr):
@@ -44,7 +48,3 @@ def _(arr):
 
     except ImportError:
         pass
-
-    @alias.register_fallback(path="asarray")
-    def _(arr):
-        return np.asarray(arr)
diff --git a/qiskit_dynamics/arraylias/register_functions/multiply.py b/qiskit_dynamics/arraylias/register_functions/multiply.py
index 9cb2f2ec1..88765821d 100644
--- a/qiskit_dynamics/arraylias/register_functions/multiply.py
+++ b/qiskit_dynamics/arraylias/register_functions/multiply.py
@@ -20,6 +20,10 @@
 def register_multiply(alias):
     """Register multiply functions to each array library."""
 
+    @alias.register_fallback(path="multiply")
+    def _(x, y):
+        return x * y
+
     @alias.register_function(lib="scipy_sparse", path="multiply")
     def _(x, y):
         return x.multiply(y)
@@ -36,7 +40,3 @@ def _(x, y):
 
     except ImportError:
         pass
-
-    @alias.register_fallback(path="multiply")
-    def _(x, y):
-        return x * y
diff --git a/qiskit_dynamics/arraylias/register_functions/to_dense.py b/qiskit_dynamics/arraylias/register_functions/to_dense.py
index 0eec3e65c..b1ecd03d3 100644
--- a/qiskit_dynamics/arraylias/register_functions/to_dense.py
+++ b/qiskit_dynamics/arraylias/register_functions/to_dense.py
@@ -29,6 +29,10 @@ def _(arr):
             return None
         return np.asarray(arr)
 
+    @alias.register_fallback(path="to_dense")
+    def _(arr):
+        return np.asarray(arr)
+
     @alias.register_function(lib="numpy", path="to_dense")
     def _(arr):
         return arr
@@ -49,7 +53,3 @@ def _(arr):
     @alias.register_function(lib="scipy_sparse", path="to_dense")
     def _(arr):
         return arr.toarray()
-
-    @alias.register_fallback(path="to_dense")
-    def _(arr):
-        return np.asarray(arr)
diff --git a/qiskit_dynamics/arraylias/register_functions/to_numeric_matrix_type.py b/qiskit_dynamics/arraylias/register_functions/to_numeric_matrix_type.py
index e57f16245..3f25a56a6 100644
--- a/qiskit_dynamics/arraylias/register_functions/to_numeric_matrix_type.py
+++ b/qiskit_dynamics/arraylias/register_functions/to_numeric_matrix_type.py
@@ -31,6 +31,10 @@ def _(arr):
             return alias().to_sparse(arr.data)
         return arr
 
+    @alias.register_fallback(path="to_numeric_matrix_type")
+    def _(arr):
+        return arr
+
     @alias.register_function(lib="numpy", path="to_numeric_matrix_type")
     def _(arr):
         return arr
@@ -51,7 +55,3 @@ def _(arr):
     @alias.register_function(lib="scipy_sparse", path="to_numeric_matrix_type")
     def _(arr):
         return arr
-
-    @alias.register_fallback(path="to_numeric_matrix_type")
-    def _(arr):
-        return arr
diff --git a/qiskit_dynamics/arraylias/register_functions/to_sparse.py b/qiskit_dynamics/arraylias/register_functions/to_sparse.py
index a79d603d1..8f5a09e64 100644
--- a/qiskit_dynamics/arraylias/register_functions/to_sparse.py
+++ b/qiskit_dynamics/arraylias/register_functions/to_sparse.py
@@ -32,6 +32,10 @@ def _(arr):
             return arr.data
         return arr
 
+    @alias.register_fallback(path="to_sparse")
+    def _(arr):
+        return csr_matrix(arr)
+
     @alias.register_function(lib="numpy", path="to_sparse")
     def _(arr):
         if arr.ndim < 3:
@@ -55,7 +59,3 @@ def _(arr):
     @alias.register_function(lib="scipy_sparse", path="to_sparse")
     def _(arr):
         return arr
-
-    @alias.register_fallback(path="to_sparse")
-    def _(arr):
-        return csr_matrix(arr)