Delta Chat cannot receive emails in private network

Mutual Help
1

Delta Chat version

Delta Chat 1.34.13 for android with the previous software version

Expected behavior

Delta Chat stays quietly in the foreground or background, it can continuously receive new email messages.

Actual behavior
Delta Chat is used under private network. A repeater is used between the private network and the public network. The repeater will periodically change the network address to prevent excessive use of data bandwidth. Android devices cannot detect a transponder’s address change. Delta Chat will lose the ability to accept new messages after staying quietly in the foreground or background for a long time or several hours.I need to toggle the data switch on the Android device or switch the network or switch from the background to the foreground, so that Delta Chat can accept new email messages again.On the Android device, Delta Chat has been excluded from power saving mode and the data switch of the application software is turned on to ensure that it runs in the background and receives data.

Steps to reproduce the problem

  1. Android devices include Android 4.4.4, Android 8, Android 9, and Android 11. They cannot receive messages after the address of the network repeater changes periodically.
  2. The problem recurs under different ISP providers’ private networks.
2

Sorry, I can’t use English very well. I use translation software to convert my native language, hoping to understand the written content.

Note: Delta Chat is used in a private network and can send encrypted messages and manage mailboxes normally. The problem is with receiving new messages. The test uses an Outlook mailbox, which is on a public network. Repeater address periodic changes affect chat software. These software include Delta Chat, lose the ability to receive messages or delay after a long period of silence.

3

Outlook and Gmail client software can normally receive new emails after the network address of the repeater changes. Delta Chat scans the inbox to read new emails, the mail server returns data loss because the client network address changes，Mail server data disorientation。