diff --git a/src/qobj/quantum_object.jl b/src/qobj/quantum_object.jl
index dcabf0d2..f231de70 100644
--- a/src/qobj/quantum_object.jl
+++ b/src/qobj/quantum_object.jl
@@ -150,7 +150,7 @@ function QuantumObject(
         type = Operator # default type
     end
 
-    if !isa(type, Operator) && !isa(type, SuperOperator) && !isa(type, Bra) && !isa(type, OperatorBra)
+    if type != Operator && type != SuperOperator && type != Bra && type != OperatorBra
         throw(
             ArgumentError(
                 "The argument type must be Operator, SuperOperator, Bra or OperatorBra if the input array is a matrix.",
@@ -187,7 +187,7 @@ function QuantumObject(
         type = Ket # default type
     end
 
-    if !isa(type, Ket) && !isa(type, OperatorKet)
+    if type != Ket && type != OperatorKet
         throw(ArgumentError("The argument type must be Ket or OperatorKet if the input array is a vector."))
     end
 
diff --git a/test/quantum_objects.jl b/test/quantum_objects.jl
index 9855897f..440817fa 100644
--- a/test/quantum_objects.jl
+++ b/test/quantum_objects.jl
@@ -24,6 +24,7 @@
     # @test_logs (:warn, "The norm of the input data is not one.") QuantumObject(a)
     @test_throws ArgumentError Qobj(a, type = Operator)
     @test_throws ArgumentError Qobj(a, type = SuperOperator)
+    @test_throws ArgumentError Qobj(a, type = OperatorBra)
     @test_throws ArgumentError Qobj(a', type = Ket)
     @test_throws DomainError Qobj(a', type = Operator)
     @test_throws DomainError Qobj(a', type = SuperOperator)
@@ -32,7 +33,7 @@
     @test_throws DomainError Qobj(a', dims = [2])
     a2 = Qobj(a', type = Bra)
     a3 = Qobj(a)
-    @test a3' == a2
+    @test dag(a3) == a2 # Here we are also testing the dag function
     @test isket(a2) == false
     @test isbra(a2) == true
     @test isoper(a2) == false
diff --git a/test/runtests.jl b/test/runtests.jl
index 049cf46c..2044736b 100644
--- a/test/runtests.jl
+++ b/test/runtests.jl
@@ -26,11 +26,11 @@ core_tests = [
     "wigner.jl",
 ]
 
-# if ((GROUP == "All") || (GROUP == "Code-Quality")) && (VERSION >= v"1.9")
-#     Pkg.add(["Aqua", "JET"])
-#     include(joinpath(testdir, "aqua.jl"))
-#     include(joinpath(testdir, "jet.jl"))
-# end
+if ((GROUP == "All") || (GROUP == "Code-Quality")) && (VERSION >= v"1.9")
+    Pkg.add(["Aqua", "JET"])
+    include(joinpath(testdir, "aqua.jl"))
+    include(joinpath(testdir, "jet.jl"))
+end
 
 if (GROUP == "All") || (GROUP == "Core")
     QuantumToolbox.about()