Why did I get incorrect wifi password pop up for unknown network on iPhone?

A few months ago my iPhone had a pop up saying 'incorrect wifi password' and telling me to enter the correct password, however it was for a network that I had never connected to or seen before. It happened when I was on safari on my 4G but wifi must have still been on. At the time I thought nothing of it but now am starting to think it was a bit odd. It hasn't happened again since.

I'm definitely sure I hadn't connected to that network before (the phone was only about a month old at the time and I'm very careful about what wifi I connect to).

I don't think my phone actually connected to the network as the incorrect password pop up appeared, I was also on a car journey at the time so wouldn't have been in range for very long.

Was wondering if anyone has any explanation for why this might have happened? Is there any risk of hacking to my phone?

The simple answer was the alert is not sensitive to a communication error from the server and lumps all Failures to authenticate into - password must be wrong.

Instead of retrying is presumes the cause of the error was human input not generating a successful challenge and response from the server.