Error message every 65 minutes from Mail App

[mills1975]

Steps to reproduce

1. Have Mail App installed
2. Setup a mail account
3. Look at the nextcloud logs

Expected behavior

No errors in the logs

Actual behavior

Have an error in the NC log exactly every 65 mins.
Tried to connect to different mailservers, the behaviour is the same with all servers, I tried.
(Self hosted Mailserver on Netcup, Managed mailserver on Hetzner)

Mail app version

5.6.8

Nextcloud version

31.0.13

Mailserver or service

Yunohost on a Netcup VPS / Webspace Mail on Hetzner

Operating system

Debian Trixie

PHP engine version

PHP 8.3

Nextcloud memory caching

Zend OPcache

Web server

Apache (supported)

Database

MariaDB

Additional info

Detailed error:
{
"reqId": "7WMsJqTF4JZ7CxLBFmCN",
"level": 3,
"time": "2026-01-22T17:40:02+00:00",
"remoteAddr": "",
"user": "--",
"app": "mail",
"method": "",
"url": "--",
"scriptName": "/home/users/xxxxxxxxxxxxxxxx/www/nextcloud/cron.php",
"message": "Cron mail sync failed for account 1",
"userAgent": "--",
"version": "31.0.13.1",
"occ_command": [
"/home/users/xxxxxxxxxxxxxxxxxx/www/nextcloud/cron.php"
],
"exception": {
"Exception": "OCA\Mail\Exception\ServiceException",
"Message": "IMAP error synchronizing account 1: Error connecting to mail server.",
"Code": 11,
"Trace": [