Describe the result once
Say whether water remains in the toilet or another fitting and whether any sound occurs. Do not keep adding water to test the response.
Identify the installed model
Different wastewater units serve different fixture combinations. The complete reference and accessible installation view help determine suitable assessment and access before work is agreed.
A useful distinction
A unit serving several fittings may receive water from more than one direction. State which fixture was last used so the assessment begins with the actual event rather than a general assumption about the toilet.