lastlog command output contains duplicate lines

AFAIK, until yesterday the output of the lastlog command contained unique lines for each user. Today I see two identical lines for root and nobody:

# lastlog
Username Port From Latest
root pts/1 10.0.0.9 Wed Jul 8 18:32:10 +0300 2020
[...]
nobody **Never logged in**
[...]
root pts/1 10.0.0.9 Wed Jul 8 18:32:10 +0300 2020
nobody **Never logged in**

I tried:

# lastlog -C -u root

and now the output is the same, except the login information for root being cleared:

# lastlog
Username Port From Latest
root **Never logged in**
[...]
nobody **Never logged in**
[...]
root **Never logged in**
nobody **Never logged in**

Why do I have duplicates in lastlog's output?

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