I have a cellphone field that is being validated as such-

```
[Required(ErrorMessage = "Cell phone is required"),
            RegularExpression(Constants.PhoneRegex, ErrorMessage = "Invalid phone number")]
public string CellPhone { get; set; }

```

This is currently being validated for US phone numbers with this regex,
`PhoneRegex = @"^(?!0+$)(\(?([0-9]{3})\)?[-. ]?([0-9]{3})[-. ]?([0-9]{4}))$";`
which I found from <https://www.oreilly.com/library/view/regular-expressions-cookbook/9781449327453/ch04s02.html>

Now there is a new requirement to not allow user to enter all zeros. So I tried `^(?!0+$)(\(?([0-9]{3})\)?[-. ]?([0-9]{3})[-. ]?([0-9]{4}))$` which I found from another thread [RegEx for phone number, all zeros not allowed](https://stackoverflow.com/questions/17985306/regex-for-phone-number-all-zeros-not-allowed)

This one works when I test it on <https://rubular.com/> but in my code it does not work

```
Example:-
Cellphone   |  Actual   |  Expected
------------------------------------
4561237890  |  //true   |  true
1234        |  //false  |  false
0000000000  |  //true   |  false

```