Content Filter - Regex

Hi all,

We are trying to create a content filter to try to prevent credit card numbers from being sent via IM.

Can anyone tell me if the plugin supports quantifiers containing commas?

For example, something simple like:

\d{13,16}

Should catch a string of 13 to 16 digits but it seems it is getting stuck on the comma.

The message on save is:

Invalid regular expression: Unclosed counted closure near index 5 \d{13 ^. Please try again.

I’m new with regular expressions - but I’m not sure what else to try, have tried escaping characters, adding quotes etc but no luck.

Any advice would be appreciated.

Thanks!