Rinse aid supports the finishing and water-runoff process described by the appliance, while detergent performs the main cleaning role. They belong in different designated compartments.
Understanding this situation
Adding rinse aid where detergent goes or using extra detergent instead does not provide the same function. The correct dose and product depend on the model and instructions.
A useful next step
Identify the compartments before filling and use only suitable products. If drying or surface marks are disappointing, review the appropriate settings rather than combining chemicals. A rinse-aid adjustment should not be used to conceal a programme that fails to complete or heat normally.
Manuals and supporting guidance
Model-specific instructions take priority. These references support the practical principles discussed here; they do not diagnose your appliance.