How can I check if a mail send with apex_mail has not bounced (solved)

Update: the bounce email was delivered two days later so it does work only a bit slow. I can't find a delete button for this question.

Hi,

I have created an apex application that sends emails to a number of persons using apex_mail. This works fine but how can I check if an email has bounced due to an non-existing email address?

I use Oracle Apex 19.1.0.00.15

I checked the APEX_190100.WWV_FLOW_USER_MAIL_LOG and can see my test mail to an non-existing email address but can't see that it bounced and have not received an bounce mail in my mailbox.