No logfiles (after moving to Portainer?)

I'm using traccar since years on my Synology using docker and everything works well.

Some weeks ago, I moved to portainer and traccer is still working fine.

But today I saw,, that I have no logfiles since weeks (in the mapped directory on my Synology). Not sure if there is a connection between moving to portainer and having no logfiles.

Here is my portainer file:

version: '3'

services:
  traccar:
    image: traccar/traccar:latest
    restart: always
    network_mode: host
    ports:
      - "8082:8082"
      - "5030:5030"
      - "5055:5055"
    volumes:
      - /volume1/docker/traccar/conf/traccar.xml:/opt/traccar/conf/traccar.xml
      - /volume1/docker/traccar/logs:/opt/traccar/conf/logs
      - /volume1/docker/traccar/data:/opt/traccar/conf/data

And my config file:

<?xml version='1.0' encoding='UTF-8'?>

<!DOCTYPE properties SYSTEM 'http://java.sun.com/dtd/properties.dtd'>

<properties>

    <entry key='config.default'>./conf/default.xml</entry>

    <entry key='database.driver'>com.mysql.jdbc.Driver</entry> 
    <entry key='database.url'>jdbc:mysql://192.168.xxx.xx:3306/traccar?serverTimezone=UTC&useSSL=false&allowMultiQueries=true&autoReconnect=true&useUnicode=yes&characterEncoding=UTF-8&sessionVariables=sql_mode=''</entry>
    <entry key='database.user'>traccar</entry> 
    <entry key='database.password'>xxxxxxxxxx</entry>

    <entry key='mail.smtp.host'>smtp.xxx.xx</entry>
    <entry key='mail.smtp.port'>587</entry>
    <entry key='mail.smtp.starttls.enable'>true</entry>
    <entry key='mail.smtp.from'>xxxxxxx</entry>
    <entry key='mail.smtp.auth'>true</entry>
    <entry key='mail.smtp.username'>xxx.xxx</entry>
    <entry key='mail.smtp.password'>xxxxxx</entry>
    
    <entry key='web.healthCheck'>false</entry>
    
    <entry key='web.console'>false</entry>
    <entry key='processing.remoteAddress.enable'>true</entry>
    <entry key='status.timeout'>1800</entry>
        
    <entry key='notificator.types'>web,mail,traccar</entry>
    <entry key='notificator.traccar.key'>xxxxxxxxx</entry>
    
</properties>

Any hint why I have no logfiles?

Was there a change in the configuration for logfiles or is my portainer config of traccar wrong?

There were no changes to the logs configuration in a while.