IME it’s normal and to be expected (and annoying and aggravating and often times infuriating).

Confusing. Seems that an unfamiliar merchant name would be suspicious.

I had a nearly identical experience with AmEx just a few weeks ago, and several with all card issuers over the past 30 years. Few weeks ago noticed an unexpected unfamiliar $16.73 charge on one of my several AmEx Biz Plats, easy to see as balances on all those accounts are usually $0.00. Called the number listed on the transaction information, some parking lot processing center, they investigated. I called again in 24 hours, was told “it’s one of our new facilities and they have several questionable charges, please report it to AmEx so they’ll investigate.” Called AmEx, card closed, new card with new # sent.

My most memorable bogus charge was 30-35 years ago, in the days of paper statements only so it was (like getting hit with 2x4) obvious to notice a statement with one exactly $300 charge from a NYC restaurant on a sock drawered card that I had used at that restaurant 9 months prior and not used again since. I suspect that some vendors process bogus charges periodically in the hope that some people will not notice and they’ll get the money.

Yup, a real pain. Consider it one of the costs of doing business playing the game (maximizing miles and points via credit cards).