Regex field validation producing false (?) negative I've also asked this question in the module issues, since I'm not sure if it is a bug or something I'm doing wrong.

I'm trying to use the Field Validation module to apply a regex control to ensure that a Philippines cell phone number is correct, and I'm getting what seems to me to be a false negative.

These numbers are 63, followed by 8 or 9, then followed by 9 digits.
I've created a control using the Regex (PCRE) rule, with the following format: 

 ^63[8-9]\d{9}$


and yet it persistently gives me false negatives, for example on this: 639121129374

I can't see anything wrong with the regex, and I've tried testing my numbers on regex101.com (cool tool) and they work fine. Is this a bug, or am I doing something wrong?
When using the PCRE validator you need to add delimiters to your regular expression. For example:

/^63[8-9]\d{9}$/