Why did he put two area codes? or is it just part of the number?

So my new boyfriend of just today (congratulate me people!! haha) gave me his cell phone number yesterday. I live in Chicago, IL and those of you who live there too should know that there are 2 are codes (773) and (312). my boyfriend put BOTH of them. so it's like this (not going to put his whole number) : 773-312-***-****

so yea.....those are either two area codes, or just a long number? any help?? and i can't ask him...its the weekend and i wanna text himWhy did he put two area codes? or is it just part of the number?
call 773-***-**** first

and then try 312-***-*** second see which on it is.

its a little odd though that he put both.Why did he put two area codes? or is it just part of the number?
Um, he probably didnt know which so threw them both in there, text the whole number, then text the others individually and see to which he answers. and if he gets them all just say a phone mistake ;)