Interviewer asked for a writing sample

Hello! I have an interview coming up for an Office Administrator and they asked for a recent writing sample. I might just be really stupid, but I'm not entirely sure what they're asking for. I don't write much aside from responding to emails. I recently created a guide on how to set up/identify a part number in a thermostat part series, but that's honestly not much. Does anyone have any advice on what they might be looking for? Any tips would be greatly appreciated