Here are the logs I've got:

[2021-07-06T17:43:30.085 CEST INFO ][           org.kde.kstars.ekos] - Websocket Message "{\"type\":\"device_property_set\",\"payload\":{\"device\":\"SynScan\",\"property\":\"CONNECTION\",\"elements\":[{\"name\":\"CONNECT\",\"state\":1},{\"name\":\"DISCONNECT\",\"state\":0}]}}"
[2021-07-06T17:43:30.147 CEST INFO ][           org.kde.kstars.indi] - SynScan :  "[INFO] Connecting to 192.168.1.109@11882 ... "
[2021-07-06T17:43:30.149 CEST DEBG ][           org.kde.kstars.indi] - SynScan : "[DEBUG] Connection successful, attempting handshake... "
[2021-07-06T17:43:30.149 CEST DEBG ][           org.kde.kstars.indi] - SynScan : "[DEBUG] CMD <Kx> "
[2021-07-06T17:43:30.153 CEST INFO ][           org.kde.kstars.indi] - SynScan :  "[ERROR] Serial read error: Read Error: Connection refused. "
[2021-07-06T17:43:30.154 CEST DEBG ][           org.kde.kstars.indi] - SynScan : "[DEBUG] Handshake failed. "
[2021-07-06T17:43:30.154 CEST DEBG ][           org.kde.kstars.ekos] - "SynScan"  is disconnected.
[2021-07-06T17:43:30.155 CEST INFO ][           org.kde.kstars.ekos] - "SynScan failed to connect.\nPlease ensure the device is connected and powered on."
 

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