stratum_recv_line failed

[sallespro]

i have successfully mined for a few hours. After a while, some errors ocasionally occurring. Now mining can not start because of this stratum_recv_line failed error.

docker service create --mode=global \
  --name miner alexellis2/cpu-opt:latest ./cpuminer \
  -a cryptonight \
  -o stratum+tcp://cryptonight.br.nicehash.com:3355 \
  -u mywallet.myworker