Facebook chat and iphone 5 issue

[geff44]

Im new to this forum and new iphone user. My girlfriend has a 32 gb iphone 5 with the latest ios update. We got this from verizon . At the moment she is using it out of the country with a local sim card. Everthing is working fine except on facebook chat she is mark offline (i.e no mobile icon). she has uninstalled and reinstalled fb a few times ...but still problem exist. Thanks for any suggestion to this issue.