I figured out why it wasn't saving, but I didn't understand why.

Why Substation is linked to its parent (plant_poi_id) when saving, but Energy Meter is not (substation_id)? Although they are identical.

For example, substation doesn’t have plant_id, but it’s okay, because his parent has, so we have a “tree tie”:

Substation create {'name': 'dasdasdas', 'plant_id': False, 'plant_poi_id': 38, 'signals': False, 'latitude': 0, 'longitude': 0, 'altitude': 0, 'tracker_ids': [], 'meteorological_data_ids': [], 'transformer_ids': [], 'first_child_energy_meter_ids': [[0, 'virtual_5', {'name': 'zzxxccdsa', 'external_source_id': False, 'latitude': 0, 'longitude': 0, 'altitude': 0, 'plant_id': False, 'substation_id': False, 'transformer_id': False, 'signals': False, 'inverter_ids': [[0, 'virtual_6', {'name': 'dasdsds', 'external_source_id': False, 'inverter_type_id': 2, 'ppc_id': False, 'plant_id': False, 'substation_id': False, 'transformer_id': False, 'energy_meter_id': False, 'latitude': 0, 'longitude': 0, 'altitude': 0, 'signals': False, 'string_box_ids': [], 'string_ids': [], 'inverter_module_ids': []}]]}]], 'first_child_inverter_ids': [[0, 'virtual_7', {'name': 'dsadsads', 'external_source_id': False, 'inverter_type_id': 2, 'ppc_id': False, 'plant_id': False, 'substation_id': False, 'transformer_id': False, 'energy_meter_id': False, 'latitude': 0, 'longitude': 0, 'altitude': 0, 'signals': False, 'string_box_ids': [], 'string_ids': [], 'inverter_module_ids': []}]]}

But energy meter doesn’t have attachment to any models:

EnergyMeter {'_id': '64b1c148ac27cd4b8f52c13f', 'name': 'zzxxccdsa', 'external_source_id': False, 'latitude': 0.0, 'longitude': 0.0, 'altitude': 0.0, 'plant_id': False, 'substation_id': False, 'transformer_id': False, 'inverter_ids': [], 'signals': False, 'id': , '__last_update': datetime.datetime(2023, 7, 14, 21, 42, 32), 'display_name': 'zzxxccdsa', 'create_uid': res.users(), 'create_date': False, 'write_uid': res.users(), 'write_date': False}