[kindly]

It has nothing to do with my bank card. It was only the use of my email for some account. I had no account on X before this point. I imagine if they used my bank card they would use another email for the account on X and not inform me of what they have done.

I already checked with my bank to make sure no money has come out. That was the first thing I did.

[anigbrowl]

Then why did your title say 'credit card fraud'? Where does the credit card come into the story?

[kindly]

I said "potential credit card fraud". Sorry for the confusion. The potential fraud is not being done to me. I just wanted to know what I should do if I suspected it.

[anigbrowl]

OK, that makes more sense. I guess it's hard to fully explain a situation in an Ask HN post.