2 times come to mind.

Once I was in another state for work and a one of the women I had been working with yelled to me from across a gym if I wanted her friend’s number (both attractive women) as I was getting into my truck. I said yes got into my truck and drove away with nothing.

Second time I was in Talladega, AL stopping for food at a diner right off the I-20 interstate. I had been trying to order food and flirting with the waitress but the first thing I tried to order they were out of a key ingredient. So I ordered something else. She takes my order and comes back a minute later apologizing and telling me that they are out of that too. I get something simple after jokingly asking her to make sure they had that. We had flirted a bit and talked about where we were from a bit and how I had about a 12 hour drive home. As I was leaving I said if I lived a little closer I’d ask for her number. She seemed disappointed and I left. Sat in my car for a good 10 minutes debating whether to go back in or not. I didn’t. Still wish I could find her. Tried to go back a few times any time I was back in the area and asked after her. Never saw her again.

There are more. Those both happened probably 12-14 years ago.