virt-who service reports an error "WebFault: Server raised fault:\u30bf\u30b9\u30af\u306f\u3001\u30e6\u30fc\u30b6\u30fc\u306b\u3088\u3063\u3066\

Issue

virt-who raises error

WebFault: Server raised fault: '\u30bf\u30b9\u30af\u306f\u3001\u30e6\u30fc\u30b6\u30fc\u306b\u3088\u3063\u3066\u30ad\u30e3\u30f3\u30bb\u30eb\u3055\u308c\u307e\u3057\u305f\u3002'
2021-03-22 15:24:23,336 [virtwho.main DEBUG] MainProcess(7210):Thread-2 @esx.py:_prepare:130 - Log into ESX
2021-03-22 15:24:23,461 [virtwho.main DEBUG] MainProcess(7210):Thread-2 @esx.py:_prepare:133 - Creating ESX event filter
2021-03-22 15:24:23,523 [virtwho.main DEBUG] MainProcess(7210):Thread-2 @virt.py:run:426 - Thread 'vcenter2' terminated
2021-03-22 15:24:23,534 [virtwho.main ERROR] MainProcess(7210):Thread-3 @esx.py:_run:203 - Waiting for ESX events fails:
Traceback (most recent call last):
.
snip
.
WebFault: Server raised fault: '\u30bf\u30b9\u30af\u306f\u3001\u30e6\u30fc\u30b6\u30fc\u306b\u3088\u3063\u3066\u30ad\u30e3\u30f3\u30bb\u30eb\u3055\u308c\u307e\u3057\u305f\u3002'
2021-03-22 15:24:23,545 [virtwho.main DEBUG] MainProcess(7210):Thread-3 @esx.py:_prepare:130 - Log into ESX
2021-03-22 15:24:23,689 [virtwho.main DEBUG] MainProcess(7210):Thread-3 @esx.py:_prepare:133 - Creating ESX event filter
2021-03-22 15:24:23,750 [virtwho.main DEBUG] MainProcess(7210):Thread-3 @virt.py:run:426 - Thread 'vcenter1' terminated
.

however guest-host mapping seems to work.