Help me, I keep popping up this error message, what's the problem?

[810106148]

^A2021-03-01T18:31:08.877+0800 WARN events events/events.go:100 listenHeadChanges quit
2021-03-01T18:31:08.877+0800 WARN events events/events.go:100 listenHeadChanges quit
2021-03-01T18:31:08.877+0800 WARN storageminer storage/wdpost_sched.go:106 window post scheduler notifs channel closed
2021-03-01T18:31:08.877+0800 ERROR miner miner/miner.go:175 failed to get best mining candidate: handler: websocket connection closed
2021-03-01T18:31:08.877+0800 ERROR storageminer storage/wdpost_sched.go:94 ChainNotify error: handler: websocket connection closed
2021-03-01T18:31:09.877+0800 INFO events events/events.go:109 restarting listenHeadChanges
2021-03-01T18:31:09.877+0800 INFO events events/events.go:109 restarting listenHeadChanges
2021-03-01T18:31:09.877+0800 ERROR events events/events.go:98 listen head changes errored: listenHeadChanges ChainNotify call failed: handler: websocket connection closed
2021-03-01T18:31:09.877+0800 ERROR events events/events.go:98 listen head changes errored: listenHeadChanges ChainNotify call failed: handler: websocket connection closed
2021-03-01T18:31:10.877+0800 INFO events events/events.go:109 restarting listenHeadChanges
2021-03-01T18:31:10.877+0800 INFO events events/events.go:109 restarting listenHeadChanges
2021-03-01T18:31:10.879+0800 WARN events events/events.go:145 tsc.add: adding current tipset failed: tipSetCache.add: expected new tipset height to be at least 542942, was 542941
2021-03-01T18:31:10.880+0800 WARN events events/events.go:145 tsc.add: adding current tipset failed: tipSetCache.add: expected new tipset height to be at least 542942, was 542941

[utgarda]

Found lots of those today, v1.9.0-rc3 , upgrading to rc5

[SgtCoin]

Archiving due to age, network is now v1.13+