zoi.acc pool not working

getting this errors

[2017-04-28 23:44:55] Stratum authentication failed
[2017-04-28 23:44:55] ...retry after 10 seconds
[2017-04-28 23:45:05] Stratum difficulty set to 0.0005
[2017-04-28 23:45:06] Stratum authentication failed
[2017-04-28 23:45:06] ...retry after 10 seconds
[2017-04-28 23:45:16] Stratum difficulty set to 0.0005
[2017-04-28 23:45:16] Stratum authentication failed
[2017-04-28 23:45:16] ...retry after 10 seconds