It is not an approved substitute for toilet paper or normal toilet waste. Long fibrous material can create a different problem from something that disperses in water.
What the observation means
Do not assume an item is safe because it is thin. The unit's mechanical action does not make every household material suitable.
A useful next step
Keep floss and similar items out of the toilet. If operation changes after something unsuitable was flushed, tell the engineer honestly. Do not continue flushing to hide the event or open the casing to untangle internal parts.
Manuals and supporting guidance
Model-specific instructions take priority. These references support the practical principles discussed here; they do not diagnose your appliance.