diff --git a/luci-app-openmptcprouter/root/usr/libexec/rpcd/openmptcprouter b/luci-app-openmptcprouter/root/usr/libexec/rpcd/openmptcprouter
index ae2e73486..727052dfa 100755
--- a/luci-app-openmptcprouter/root/usr/libexec/rpcd/openmptcprouter
+++ b/luci-app-openmptcprouter/root/usr/libexec/rpcd/openmptcprouter
@@ -755,7 +755,7 @@ function interfaces_status()
 							mArray.openmptcprouter["ss_traffic"] = vpsinfo.shadowsocks.traffic or ""
 						end
 						if vpsinfo.vps.time ~= "" then
-							if os.time() - vpsinfo.vps.time > 10 then
+							if math.abs(os.time() - vpsinfo.vps.time) > 10 then
 								mArray.openmptcprouter["vps_time_accurate"] = false
 							else
 								mArray.openmptcprouter["vps_time_accurate"] = true