[Migrants sleep on train tracks near the makeshift refugee camp at the northern Greek border point of Idomeni, Greece, Monday, March 28, 2016. Over 11,000 refugees and migrants stranded at this makeshift encampment, some for weeks, after Balkan countries on what used to be the busiest migrant route to central and northern Europe shut down their borders. (AP Photo/Darko Vojinovic)]ATHENS, Greece (AP) — Greece's government is appealing to volunteers and aid groups working with desperate refugees on the border to make sure the migrants don't get misinformation like reports that led hundreds to leave a refugee camp on a failed, hours-long trek to try to enter Macedonia.