Can you text/Call in the Bahamas with AT&T?

My girlfriend is in the Bahamas she has AT&T, I haven't heard from her. She has iPhone, when I text her like iMessage it was taking a while to say delivered and when I call her phone i hear nothing and it goes to voicemail or I'll hear a dial tone then to voicemail.Could it be no reception?

You can, as AT&T do operate there, however If as you say no response from the servers or a delay then she must be in a remote area, remember that iMessage operates on an internet level, if no answer calling her, must be in an area where AT&T can't reach even in 2G. Its not uncommon.

She doesn't have International Roaming activated so when you call her, it's taking to her voicemail.IMessages work on cellular data or Wi-Fi data so it's working whenever she's in Wi-Fi range.