diff --git a/pynestml/cocos/co_co_each_block_defined_at_most_once.py b/pynestml/cocos/co_co_each_block_defined_at_most_once.py
index 66b479c18..1fd6d2bf7 100644
--- a/pynestml/cocos/co_co_each_block_defined_at_most_once.py
+++ b/pynestml/cocos/co_co_each_block_defined_at_most_once.py
@@ -48,30 +48,12 @@ def check_co_co(cls, node: ASTModel):
         Checks whether each block is define at most once.
         :param node: a single neuron or synapse.
         """
-        if len(node.get_state_blocks()) > 1:
-            code, message = Messages.get_block_not_defined_correctly('State', False)
-            Logger.log_message(code=code, message=message, node=node, error_position=node.get_source_position(),
-                               log_level=LoggingLevel.ERROR)
         # check that update block is defined at most once
         if len(node.get_update_blocks()) > 1:
             code, message = Messages.get_block_not_defined_correctly('Update', False)
             Logger.log_message(code=code, message=message, node=node, error_position=node.get_source_position(),
                                log_level=LoggingLevel.ERROR)
-        # check that parameters block is defined at most once
-        if len(node.get_parameters_blocks()) > 1:
-            code, message = Messages.get_block_not_defined_correctly('Parameters', False)
-            Logger.log_message(code=code, message=message, node=node, error_position=node.get_source_position(),
-                               log_level=LoggingLevel.ERROR)
-        # check that internals block is defined at most once
-        if len(node.get_internals_blocks()) > 1:
-            code, message = Messages.get_block_not_defined_correctly('Internals', False)
-            Logger.log_message(code=code, message=message, node=node, error_position=node.get_source_position(),
-                               log_level=LoggingLevel.ERROR)
-        # check that equations block is defined at most once
-        if len(node.get_equations_blocks()) > 1:
-            code, message = Messages.get_block_not_defined_correctly('Equations', False)
-            Logger.log_message(code=code, message=message, node=node, error_position=node.get_source_position(),
-                               log_level=LoggingLevel.ERROR)
+
         # check that input block is defined at most once
         if len(node.get_input_blocks()) > 1:
             code, message = Messages.get_block_not_defined_correctly('Input', False)
@@ -81,6 +63,7 @@ def check_co_co(cls, node: ASTModel):
             code, message = Messages.get_block_not_defined_correctly('Input', True)
             Logger.log_message(code=code, message=message, node=node, error_position=node.get_source_position(),
                                log_level=LoggingLevel.WARNING)
+
         # check that output block is defined at most once
         if len(node.get_output_blocks()) > 1:
             code, message = Messages.get_block_not_defined_correctly('Output', False)
diff --git a/pynestml/utils/messages.py b/pynestml/utils/messages.py
index ef4d62207..0a6093ac5 100644
--- a/pynestml/utils/messages.py
+++ b/pynestml/utils/messages.py
@@ -552,24 +552,22 @@ def get_continuous_input_port_specified(cls, name, keyword):
         return MessageCode.CONTINUOUS_INPUT_PORT_WITH_QUALIFIERS, message
 
     @classmethod
-    def get_block_not_defined_correctly(cls, block, missing):
+    def get_block_not_defined_correctly(cls, block: str, missing: bool) -> Tuple[MessageCode, str]:
         """
         Indicates that a given block has been defined several times or non.
         :param block: the name of the block which is not defined or defined multiple times.
-        :type block: str
         :param missing: True if missing, False if multiple times.
-        :type missing: bool
-        :return: a message
-        :rtype: (MessageCode,str)
         """
         assert (block is not None and isinstance(block, str)), \
             '(PyNestML.Utils.Message) Not a string provided (%s)!' % type(block)
         assert (missing is not None and isinstance(missing, bool)), \
             '(PyNestML.Utils.Message) Not a bool provided (%s)!' % type(missing)
+
         if missing:
             message = block + ' block not defined!'
         else:
             message = block + ' block defined more than once!'
+
         return MessageCode.BLOCK_NOT_CORRECT, message
 
     @classmethod
diff --git a/tests/nest_tests/resources/multiple_state_and_parameter_blocks.nestml b/tests/nest_tests/resources/multiple_state_and_parameter_blocks.nestml
new file mode 100644
index 000000000..cb358d271
--- /dev/null
+++ b/tests/nest_tests/resources/multiple_state_and_parameter_blocks.nestml
@@ -0,0 +1,12 @@
+model multiple_state_and_parameter_blocks:
+    parameters:
+        a integer = 42
+
+    state:
+        x integer = a
+
+    parameters:
+        b integer = a * x
+
+    state:
+        y integer = a * x * b