"That 'LOST CONNECTIVITY' error on Galaxy Dimension panels is often a timing issue between the Ethernet module (Iris) and the app's secure handshake. Have you checked if the encryption key in the panel matches the app exactly? Sometimes a slight firmware mismatch on the Iris 4 can also cause the session to drop after the initial connection.
In our testing at CIVINTEC, we’ve noticed that ensuring a stable static IP and checking the polling intervals can sometimes stabilize these remote sessions. If the hardware continues to be temperamental, it might be worth looking into readers or controllers that support more robust OSDP v2 protocols for a more reliable secure channel. Hope you get it sorted!"