It’s an authentication problem for sure:
2020-02-12 01:02:48 5175 [HttpClient] --> PROPFIND https://emma.cloud.tabdigital.eu/remote.php/dav
2020-02-12 01:03:14 5175 [HttpClient] <-- 401 https://emma.cloud.tabdigital.eu/remote.php/dav (25404ms)
2020-02-12 01:03:14 5175 [HttpClient] <?xml version="1.0" encoding="utf-8"?>
<d:error xmlns:d="DAV:" xmlns:s="http://sabredav.org/ns">
<s:exception>Sabre\DAV\Exception\NotAuthenticated</s:exception>
<s:message>No public access to this resource., Username or password was incorrect, No 'Authorization: Bearer' header found. Either the client didn't send one, or the server is mis-configured, Username or password was incorrect</s:message>
</d:error>
Well of course there is no password in the logs. Which authentication method do you use in Nextcloud? Local auth, LDAP? 2FA?
Can you provide a test account where I can reproduce this?