RegEx help for layer 7 filter

RouterOS General
1

Hi,

I would like to match DNS query for domain that start with 3 numeric follow to 3 non numeric follow with .com

I try this : \d{3}?\D{3}?.com
to match 515kkk.com or 202aaa.com…

But It not maching in my rOS.

need help

thanks

Armand