EF0/EFO on Electrolux may be accompanied by a leak, excess suds, or an unbalanced load. EF3 is identified as leak detection in the referenced support source.
Priority goes to a water leak
The manufacturer documentation does not attribute this entire family solely to detergent. If you see water coming out, stop using it and shut off the supply. Avoid touching the plug if there is moisture or water around it.
Check the outside of the drawer, filter connection, hoses, and door edge. A trapped garment can prevent the gasket from seating properly, but seeing it does not rule out other leaks. Do not tilt the washer to empty an internal tray.
If there is no visible leak
With plenty of suds, check the dose and the added products, and follow the recovery time in the manual. Clean the drawer only through the user access if there is buildup. If there are no suds, but the laundry is bunched up, wait for normal opening and correct the distribution within the program capacity.
Record which condition you found. If the warning comes back or you cannot locate the leak, request a diagnosis with the PNC and the full code. If the condition is limited to suds, see how to fix excess suds.
Do not run another cycle to check whether EF3 clears while water is still appearing.