Mautic✉fetch throws an error

Your software
*Mautic 4.4.10
My PHP version is : 8.1
My MySQL/MariaDB version is 10.6.12-MariaDB-0ubuntu0.22.04.1 - mysqli

Updating/Installing Errors
there were no errors at installation

These errors are showing in the installer :
there were no errors

These errors are showing in the Mautic log :
[2023-10-08 09:55:02] mautic.WARNING: Command mautic:email:fetch exited with status code 1 {“hostname”:“”,“pid”:1756376}
[2023-10-08 10:00:02] mautic.NOTICE: Error: Call to undefined function Mautic\EmailBundle\MonitoredEmail\imap_search() (uncaught exception) at /home/users/kstrohmaier/www/ledamstiel/u/app/bundles/EmailBundle/MonitoredEmail/Mailbox.php line 542 while running console command mautic:email:fetch {“hostname”:“”,“pid”:1756902}

Your problem
My problem is : i set up the cron-job mautic:emails:fetch. the test found no errors, then i configured mautic to read the inbox of my imap server, with success. the cron job triggers every 5 minutes and i receive an error- mail:

In Mailbox.php line 542:
Attempted to call function “imap_search” from namespace “Mautic\EmailBundle

Steps I have tried to fix the problem : nothing

thank you for your help
Klaus :grinning: