Mail Notification don´t work

Hello dear community,
I have a problem setting up the mail client.
The notificator.traccar.key works without any issues.
I have a Ubuntu server at Hetzner, which is only used for Traccar.
The firewall is disabled.
In the notification settings, I can only select the Traccar channel. The email option does not appear.
The server has been restarted.
What else can I check?

Thank you very much for your help.
Best regards,
Here is the traccar.xml config (XXXX has been correctly replaced with my own values).

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE properties SYSTEM 'http://java.sun.com/dtd/properties.dtd'>
<properties>
<entry key='database.driver'>com.mysql.cj.jdbc.Driver</entry>
<entry key='database.url'>jdbc:mysql://localhost/traccar?zeroDateTimeBehavior=round&serverTimezone=UTC&allowPublicKeyRetrieval=true&useSSL=false&allowMultiQueries=true&autoReconnect=true&useUnicode=yes&characterEncoding=UTF-8&sessionVariables=sql_mode=''</entry>
<entry key='database.user'>root</entry>
<entry key='database.password'>root</entry>
<entry key='notificator.types'>traccar,...</entry>
<entry key='notificator.traccar.key'>XXXXXXXXXXXXXXXXXXXXXXXX</entry>
<entry key='mail.smtp.host'>send.one.com</entry>
<entry key='mail.smtp.port'>587</entry>
<entry key='mail.smtp.ssl.enable'>true</entry>
<entry key='mail.smtp.from'>XXXXXXXXXXXXXXXXXXXXXXXX@XXXXXXXXXXXXXXXXXXXXXXXX.de</entry>
<entry key='mail.smtp.auth'>true</entry>
<entry key='mail.smtp.username'>XXXXXXXXXXXXXXXXXXXXXXXX@XXXXXXXXXXXXXXXXXXXXXXXX.de</entry>
<entry key='mail.smtp.password'>XXXXXXXXXXXXXXXXXXXXXXXX</entry>
</properties>

Your notificator.types configuration doesn't make sense to me.

That's embarrassing. But forgivable for a beginner. THANK YOU.

Now it´s

<entry key='notificator.types'>traccar,mail, web</entry>