Why did my older coworker keep saying this over and over?

He was saying ‘I did such and such for you’ (it’s a basic part of his job and it wasn’t specifically for me, he’s just adding that part in to be dramatic) and I would say ‘thank you’ and then he would repeat himself. And after every response of mine he kept saying the same thing. I’m like ok weirdo in my head.

I could tel he was playing cause he laughed after but I don’t get why he was doing it other than he wanted to let off steam.

Why did my older coworker keep saying this over and over?
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