I used to work for an ISP
Back in the 1990's, before the Internet was particularly wide spread, I used to work for one of the bigger ISP's.
I'd been there so long, I was asked to literally 'write the book' on how the DNS systems worked, with instructions on how the data was propagated, how each server talked to each other, and the types of resource record that could be created.
Sadly, the dotcom bust happened and I was out of a job.
Some six months later, to make it easier to do things, I needed a new TXT RR created in the DNS zone file.
So I called up the new Tech Support team.
And told them precisely what to write in the file, down to the last full stop.
"Ma'am, we can't do that, it would be an illegal entry in the DNS Zone file."
"Oh, but you can do this. I know you can."
"Ma'am, I'm sorry, but it's not possible."
"I see. May I speak to your manager, John Smith?" (I knew he still worked there!)
"Yes, may I take your name so that I can pass the message on correctly?"
Don't know why he hadn't asked this so far, but eh... it happens.
"Lisa Lyons"
You could hear the silence, as if gears were slowly grinding....
"Where do I know that name from?"
"Take a look at the bottom of your DNS training document!"
"OOOOOOOOHHHH!!!"
"And if you read page 12, paragraph 8, you will find that it IS possible to add the record I need you do add."
"Errrmmm.... I'm sorry."