Regex how to match everything that doesn't follow the format with 3 digits followed by a dash then 4 digits?

\d{3}-\d{4}
This one matches something like 123-4567

So I change it to ^(?!(\d{3}-\d{4})). But it doesn’t match anything.

I got a list of phone numbers like

123-4567
NOW-4-WAX
12 345 67 89

I would like to match anything except the format xxx-xxxx where x is a digit.

>Solution :

If you add .* to the end of your regex, it should match any line that does not start with a phone number in the 123-4567 format.

Demo on RegExr: ^(?!(\d{3}-\d{4})).*$

It’s worth noting that if you have anything in your input file that is not a phone number at all, this will match those too.