I've a ton of these

I used to operate a busy hospital switchboard. Often, in response to the question, "The line is busy, do you wish to hold?" the callers would ask, "How long will they be?" I was b0110cked for a rhetorical "How long is a piece of string?" and so from then on answered, "Only until they've finished their conversation!" This seemingly gave them enough thinking time from their response, "Yes, but how ... OK"!
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In my youth I worked in a hotel The pest control guy came in and was strategically placing the boxes of poison. Written on the box (about the size of a small box of tablets) in big, bright red letters was printed "POISON: DO NOT EAT" - big enough to cover the entire surface.
"Isn't that counter-productive?" I asked.
"What do you mean?" asked the puzzled pest control guy.
"Well, the mice will know not to ... never mind."
(Yes, in Colin's world, mice can read!)
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Working as a medical secretary (different hospital) I was audio-typing a letter to Dr Jefferies. The dictation began, "Dear Steven" ... or was it Stephen?
I looked through the patient's notes to see if there was a clue on previous correspondence, but nothing. So eventually I just rang the surgery.
"Does Dr Jefferies spell his name with a PH or a V?" I asked.
"Neither. Double-F." came the reply.
Medical receptionists!
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This isn't so much a stupid question as my potentially all-time embarrassing moment, but it just seems to fit with these other stories.
One morning, I realised I was going to be late. I hadn't been sure of the bus times but it was now too late to walk and there was no sign of a bus. Private hire cars aren't supposed to stop (you need to call and book), but they often will. So I tried flagging one down.
Eventually, a car stopped and I jumped in. "Could you take me into the town centre?" I asked nicely.
"OK." said the driver.
When we were getting close, he asked where I'd like dropping off. "Is it OK to go on to the next set of lights?" I asked nicely - and I don't mind admitting that I was rather hoping he might not charge me, since he was driving into town anyway, presumably returning to the taxi office.
When we approach the lights, I tentatively asked, "What do I owe you?"
"Oh, nothing, that's OK." he said to my relief.
"That's very kind of you." I said, thanking him and then asked for his card.
"Card? What card?" he asked, puzzled.
"Your firm's card, so I can use this taxi company next time I need one." I clarified.
"I'm not a taxi." said the bemused driver!
Exit crimson Colin!
I was quiet that morning at work and the supervisor eventually asked me what was wrong. I hadn't realised I'd been so quiet and when I told them, the laughter could be heard upstairs!