Problems with redirecting mails from Calibre

Hello sinds I am using Calibre to organise my ebooks.
Before I was using Avast VPN it was possible for me to sent my ebooks via Calibre to my email account . When received there plcae it in books on my iPad.
What can be thr problem? I tryed it with VPN on and off but no result.
Do I have to change something in the settings ???

Can somebody help me with this?

Thanks in advance.