How can blocks change from Unsealed to Sealed?

Today I tried to start mining with lotus. However, storage list shows that, 1 block in Unsealed state for several hours, but cannot change to sealed.

jjxx@jjxx:~/git/lotus$ lotus-storage-miner --storagerepo=/data/hdd1/lotuswork/lotusstorage/ storage list
b218c65c-17ab-4cec-b4c2-a5ec6ba5d3e3:
[|| ] 2.703 TiB/50.73 TiB 5%
Unsealed: 1; Sealed: 0; Caches: 0
Weight: 10; Use: Seal Store
Local: /data/hdd1/lotuswork/lotusstorage/
URL: http://127.0.0.1:2345/remote
jjxx@jjxx:~/git/lotus$ du -h /data/hdd1/lotuswork/lotusstorage/
12K /data/hdd1/lotuswork/lotusstorage/keystore
28K /data/hdd1/lotuswork/lotusstorage/datastore/metadata
20K /data/hdd1/lotuswork/lotusstorage/datastore/client
20K /data/hdd1/lotuswork/lotusstorage/datastore/staging
20K /data/hdd1/lotuswork/lotusstorage/datastore/chain
92K /data/hdd1/lotuswork/lotusstorage/datastore
33G /data/hdd1/lotuswork/lotusstorage/unsealed
97G /data/hdd1/lotuswork/lotusstorage/cache/s-t0109808-0
97G /data/hdd1/lotuswork/lotusstorage/cache
33G /data/hdd1/lotuswork/lotusstorage/sealed
161G /data/hdd1/lotuswork/lotusstorage/

jjxx@jjxx:~/git/lotus$ ls -ltr /data/hdd1/lotuswork/lotusstorage/*
-rw-r–r-- 1 jjxx jjxx 90 Jun 21 08:15 /data/hdd1/lotuswork/lotusstorage/storage.json
-rw-r–r-- 1 jjxx jjxx 105 Jun 21 08:15 /data/hdd1/lotuswork/lotusstorage/sectorstore.json
-rw-rw-r-- 1 jjxx jjxx 642 Jun 21 08:15 /data/hdd1/lotuswork/lotusstorage/config.toml
-rw-rw-r-- 1 jjxx jjxx 0 Jun 21 08:21 /data/hdd1/lotuswork/lotusstorage/repo.lock
-rw------- 1 jjxx jjxx 136 Jun 21 08:23 /data/hdd1/lotuswork/lotusstorage/token
-rw-r–r-- 1 jjxx jjxx 28 Jun 21 08:23 /data/hdd1/lotuswork/lotusstorage/api

/data/hdd1/lotuswork/lotusstorage/datastore:
total 16
drwx------ 2 jjxx jjxx 4096 Jun 21 08:21 staging
drwxr-xr-x 2 jjxx jjxx 4096 Jun 21 08:21 metadata
drwx------ 2 jjxx jjxx 4096 Jun 21 08:21 client
drwx------ 2 jjxx jjxx 4096 Jun 21 08:21 chain

/data/hdd1/lotuswork/lotusstorage/keystore:
total 8
-rw------- 1 jjxx jjxx 130 Jun 21 08:15 NRUWE4BSOAWWQ33TOQ
-rw------- 1 jjxx jjxx 86 Jun 21 08:23 MF2XI2BNNJ3XILLQOJUXMYLUMU

/data/hdd1/lotuswork/lotusstorage/unsealed:
total 33554440
-rw-r–r-- 1 jjxx jjxx 34359738379 Jun 21 08:39 s-t0109808-0

/data/hdd1/lotuswork/lotusstorage/sealed:
total 33554436
-rw-r–r-- 1 jjxx jjxx 34359738368 Jun 21 08:40 s-t0109808-0

/data/hdd1/lotuswork/lotusstorage/cache:
total 4
drwxr-xr-x 2 jjxx jjxx 4096 Jun 21 11:29 s-t0109808-0

latest log of “lotus-storage-miner run”:

2020-06-21T13:31:45.483Z WARN dht/RtRefreshManager rtrefresh/rt_refresh_manager.go:191
failed when refreshing routing table {“error”: “2 errors occurred:\n\t* failed to query for self, err=failed to run refresh DHT query for key=\u0000$\u0008\u0001\u0012 \u001d\u0000\r\ufffd\u0010Ա7\u0005\ufffd\ufffdx\ufffd<Q\ufffdm\ufffd3\ufffd\ufffd\u0001\ufffd\u0019\tX\ufffd\ufffd-姧, err=failed to find any peer in table\n\t* failed to refresh cpl=0, err=failed to run refresh DHT query for key=\u0012 \u0000\u0001k\u000c\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000, err=failed to find any peer in table\n\n”}
2020-06-21T13:35:25.743Z WARN storageminer storage/wdpost_sched.go:216 Aborting Window PoSt (Deadline: &{CurrentEpoch:8773 PeriodStart:6661 Index:22 Open:8773 Close:8869 Challenge:8753 FaultCutoff:8753})
2020-06-21T13:35:25.743Z INFO storageminer storage/wdpost_sched.go:200 at 8869, doPost for P 6661, dd 23
2020-06-21T13:35:25.783Z INFO storageminer storage/wdpost_run.go:366 di: {CurrentEpoch:8869 PeriodStart:6661 Index:23 Open:8869 Close:8965 Challenge:8849 FaultCutoff:8849}
2020-06-21T13:35:25.783Z INFO storageminer storage/wdpost_run.go:367 dc: 0
2020-06-21T13:35:25.783Z INFO storageminer storage/wdpost_run.go:368 fp: 0
2020-06-21T13:35:25.783Z INFO storageminer storage/wdpost_run.go:369 pc: 0
2020-06-21T13:35:25.783Z INFO storageminer storage/wdpost_run.go:370 ts: {bafy2bzacebno2owyjudx7ramutef6dem56sseowh7olapojhke22ezgfibhv2} (8869)

2020-06-21T13:41:45.481Z INFO dht/RtRefreshManager rtrefresh/rt_refresh_manager.go:265
starting refreshing cpl 0 with key &! (routing table size was 0)
2020-06-21T13:41:45.481Z WARN dht/RtRefreshManager rtrefresh/rt_refresh_manager.go:191
failed when refreshing routing table {“error”: “2 errors occurred:\n\t* failed to query for self, err=failed to run refresh DHT query for key=\u0000$\u0008\u0001\u0012 \u001d\u0000\r\ufffd\u0010Ա7\u0005\ufffd\ufffdx\ufffd<Q\ufffdm\ufffd3\ufffd\ufffd\u0001\ufffd\u0019\tX\ufffd\ufffd-姧, err=failed to find any peer in table\n\t* failed to refresh cpl=0, err=failed to run refresh DHT query for key=\u0012 \u0000\u0000&!\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000, err=failed to find any peer in table\n\n”}

Any suggestion is appreciated.