I am having something like this 

root@worker:/home/user/btm-miner# ./miner -user 0x3fD23AfC8f59A5b426175FD199b4b1658C54f7C1.text
2018/05/26 16:24:33 fserver :  true
getGpuCount error:0

Init GPU Device 0: "GeForce GTX 1060 6GB" with compute capability 6.1


Init GPU Device 1: "GeForce GTX 1060 6GB" with compute capability 6.1


Init GPU Device 2: "GeForce GTX 1060 6GB" with compute capability 6.1

2018/05/26 16:24:35 Starting BTM mining
2018/05/26 16:24:35 Connecting to btm.uupool.cn:9220
2018/05/26 16:24:35 2 - Initializing
2018/05/26 16:24:35 2 - No work ready
2018/05/26 16:24:35 0 - Initializing
2018/05/26 16:24:35 0 - No work ready
2018/05/26 16:24:35 1 - Initializing
2018/05/26 16:24:35 1 - No work ready
2018/05/26 16:24:36 Error in connection to stratumserver: EOF, retry in 10s...
2018/05/26 16:24:36 Unable to login: Invalid login
panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x8 pc=0x5cace2]

goroutine 27 [running]:
github.com/leifjacky/btmgominer/clients/stratum.(*Client).Close(0x0)
   /data/go/src/github.com/leifjacky/btmgominer/clients/stratum/stratum.go:94 +0x22
github.com/leifjacky/btmgominer/algorithms/bytom.(*StratumClient).Start(0xc42014e000)
   /data/go/src/github.com/leifjacky/btmgominer/algorithms/bytom/siastratum.go:119 +0x64a
github.com/leifjacky/btmgominer/algorithms/bytom.(*Miner).createWork(0xc420072540)
   /data/go/src/github.com/leifjacky/btmgominer/algorithms/bytom/miner.go:85 +0xcc
created by github.com/leifjacky/btmgominer/algorithms/bytom.(*Miner).Mine
   /data/go/src/github.com/leifjacky/btmgominer/algorithms/bytom/miner.go:57 +0x9d