A clear description helps a service team understand what you are experiencing and what information may still be needed. You do not need to diagnose the fault yourself.
Start with the equipment
Note the equipment type and, if easy to find, its manufacturer and model. Mention where it is used and what it is connected to. A photo of the outside label or display can be useful when it is safe to take one.
Describe what changed
Explain what the device was doing before the issue, what it is doing now, when you first noticed the change, and whether it happens all the time or only in certain conditions. Include any message or indicator shown on the display.
Include context, not guesses
Share any checks already completed and relevant recent changes, such as a new installation or a change in how the equipment is used. It is fine to say that you are unsure about the cause.