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Error Log says:

[Fri Feb 12 10:23:50.780840 2021] [core:error] [pid 5868:tid 2040] (20024)The given path is misformatted or contained invalid characters: [client XXX.XXX.XXX:60799] AH00127: Cannot map GET /Cloud:443/status.php HTTP/1.1 to file
[Fri Feb 12 10:23:50.865851 2021] [core:error] [pid 5868:tid 2040] (20024)The given path is misformatted or contained invalid characters: [client XXX.XXX.XXX:60799] AH00127: Cannot map GET /Cloud:443 HTTP/1.1 to file
[Fri Feb 12 10:23:50.934847 2021] [core:error] [pid 5868:tid 2040] (20024)The given path is misformatted or contained invalid characters: [client XXX.XXX.XXX:60799] AH00127: Cannot map GET /Cloud:443/status.php HTTP/1.1 to file

And nextcloud says:
403 forbidden for "GET https://myip:443/Cloud/status.php"

It says unknown custom route.

I'm using Apache with php7.4 on Win Server 2019