On the Miele W2 generation, a TwinDos cartridge may not be recognized if the barcode the appliance reads is missing. Check the generation before applying this procedure.
Recognition before consumption
The manufacturer documentation explicitly refers to W2. If the cartridge appears accepted but is not being used up, the issue follows a different path; do not alter its label in an attempt to change the dosing.
Visually check the newly installed cartridge and whether it matches your washer’s system. Keep the packaging and record the exact message shown on the panel. An illegible or missing code does not let you conclude that the machine’s reader is faulty.
Set the reference value in compatible W2
The official help lets you go into Settings, Appliance functions, and TwinDos; select the compartment and the medium-soiling reference value, and enter the dosing amount. That amount is taken from the packaging for the load and reference hardness specified by the model, not from a generic figure for all detergents.
If your panel does not match that path, consult the manual for the corresponding generation. If recognition keeps failing, contact Miele with the model and the cartridge details. Do not tamper with labels or force the slots.
Setting a reference dose does not authorize using an incompatible cartridge.