International Calling "Service Temporarily Unavailable"

I have a straight talk home phone and pay for the international calling plan. For the last 2 weeks I have not been able to make any international calls. When I dial the access number 1-646-982-0992 there is immediately a recording that says "Temporarily out of service." I have called Straight Talk for support twice but they haven't been any help. The only suggestion they make is to reboot my phone by unplugging it. Clearly the issue is not with my device as I am able to make local calls with no issue. Is anyone else getting this recording when dialing the access number 1-646-982-0992?