QGIS - Crashes upon selecting discard

Question

I am using qgis 3.18 and I run the following code in python console.

layer = QgsProject.instance().mapLayersByName("my_layer")[0]
iface.setActiveLayer(layer)
# Define a function called when a feature is added to the layer
def feature_added(fId):
    # Disconnect from the signal
    layer.featureAdded.disconnect()
    layer.select(fId)
    features = layer.selectedFeatures()
    for f in features:
        f['type'] = 'D'
        f['surface'] = 'FW'
        f['material'] = 'Modular Surface'
        layer.updateFeature(f)
    layer.removeSelection()
    # Save changes and end edit mode
    layer.commitChanges()
    # disaable supress
    formConfig.setSuppress(0)
    layer.setEditFormConfig(formConfig)
    
    
# Connect the layer to the signal featureAdded, so when a feature is
# added to the layer, the feature_added function is called    
layer.featureAdded.connect(feature_added)

# Set the layer in edit mode
layer.startEditing()

formConfig = layer.editFormConfig()
formConfig.setSuppress(1)
layer.setEditFormConfig(formConfig)

# Activate the QGIS add feature tool
iface.actionAddFeature().trigger()

When I run this tool, it works fine and captures the feature in my_layer. Now I do the following operation soon after running the above tool:

• I manually make the layer editable.
• Add a line feature
• Stop editing
• Discard changes

QGIS Crashes! What is wrong in the code??