Somebody posted a similar comment above yours (somewhere...). I don't think your experience is unique!

I had email correspondence once with a vendor about how to talk to their i2c bus. The documentation was all asm, and I wanted to at least “uplift” to C. They didn’t have any answers, so I sent them my solution which was was the asm calls that the c stdlib decompiled into.

4 years later my company had bought a different company, who happened to be using a newer model of the same board. They asked me how we could use the 12c bus. “Well before you bought us, we emailed the vendor and sent back this C snippet”

It was my code, verbatim. I’ve always wondered how many times they passed that bit of code around.

It was funny for me, when I asked it about something specific exotic - and it gave me a confident answer. But checking the sources I discovered it was from my own inquiries on a forum thread about it from the last time I unsuccesfully tried this (before the agents came) And so I knew, that any authorative tone was undeserved.

On the other hand, Claude later nailed this project, where I as a human said before, no, too much extra work.

Well, it's a plagiarizing machine after all and most of the time it remixes it well enough so most people can't tell.