RPC Error: method 'Filecoin.WalletList' not found

[weforu]

Describe the bug
Suddenly, this error message appeared on miner log.
I do not know Who is IP 171.88.42.138:56089. It is not mine.
What happened?

To Reproduce
Steps to reproduce the behavior:

1. Run '...'
2. 2020-11-13T12:35:43.397+0900 ERROR rpc [email protected]/server.go:87 RPC Error: method 'Filecoin.WalletList' not found
   2020-11-13T12:35:43.398+0900 WARN rpc [email protected]/server.go:93 rpc error: method 'Filecoin.WalletList' not found
   2020-11-13T12:35:43.708+0900 WARN auth auth/handler.go:39 JWT Verification failed (originating from 171.88.42.138:56089): JWT Verification failed: jwt: malformed token

Expected behavior
A clear and concise description of what you expected to happen.

Screenshots
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Version (run lotus version):
Daemon: 1.1.2+git.d4cdc6d33+api0.17.0
Local: lotus version 1.1.2+git.d4cdc6d33

Additional context
Add any other context about the problem here.

[weforu]

2020-11-13T13:02:00.701+0900 WARN auth auth/handler.go:39 JWT Verification failed (originating from 222.211.162.132:59457): JWT Verification failed: jwt: malformed token
2020-11-13T13:02:00.725+0900 INFO rpc [email protected]/client.go:346 rpc output message buffer {"n": 2}
2020-11-13T13:02:00.998+0900 ERROR rpc [email protected]/server.go:87 RPC Error: method 'Filecoin.WalletList' not found
2020-11-13T13:02:00.998+0900 WARN rpc [email protected]/server.go:93 rpc error: method 'Filecoin.WalletList' not found
2020-11-13T13:02:01.320+0900 WARN auth auth/handler.go:39 JWT Verification failed (originating from 222.211.162.132:59494): JWT Verification failed: jwt: HMAC verification failed

[jennijuju]

more a discussion Q&A topic instead of a lotus issue. Converting to discussion.