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Sx1302 packet forvarder downlink received

Hello!

I am seeing strange behavior.
After receiving a downlink from server, packet forwarder send downlink packet to device:

JSON down: {“txpk”:{“imme”:true,“freq”:869.1,“rfch”:0,“powe”:27,“modu”:“LORA”,“datr”:“SF12BW125”,“codr”:“4/5”,“ipol”:true,“size”:15,“data”:“YI+WBDgA5QDA/1zxgmnt”},“ltx_tx”:{“eui”:“04:97:90:00:10:61:1B:D8”,“t”:1668510124915}}
INFO: [down] a packet will be sent in “immediate” mode
INFO: PULL_X 12 bytes sent to port 10040

And then receives the same packet as uplink:

INFO: Received pkt from mote: 3804968F (fcnt=229)

JSON up: {“rxpk”:[{“jver”:1,“tmst”:2129716695,“chan”:8,“rfch”:1,“freq”:868.300000,“mid”:16,“stat”:1,“modu”:“LORA”,“datr”:“SF12BW125”,“codr”:“4/5”,“rssis”:-65,“lsnr”:2.8,“foff”:35,“rssi”:-64,“size”:15,“data”:“YI+WBDgA5QDA/1zxgmnt”}]}
INFO: [up] PUSH_ACK received in 2 ms

After that, he received a regular package from device:

INFO: Received pkt from mote: 3804968F (fcnt=5278)

JSON up: {“rxpk”:[{“jver”:1,“tmst”:2133029544,“chan”:2,“rfch”:0,“freq”:867.500000,“mid”: 8,“stat”:1,“modu”:“LORA”,“datr”:“SF8BW125”,“codr”:“4/5”,“rssis”:-70,“lsnr”:10.2,“foff”:495,“rssi”:-70,“size”:23,“data”:“QI+WBDgAnhTAu3SA6BQbueiwDve4Fc0=”}]}
INFO: [up] PUSH_ACK received in 2 ms

If i disable the devise or set ipol to false, i dont see the regular uplink. But the copy of downlink packet receved anyway.

This behavior occurs on 2 different platforms.

“chan_Lora_std”: {
“enable”: true,.
“radio”: 1,.
“if”: -400000,.
“bandwidth”: 125000,.
“spread_factor”: 12,
“implicit_hdr”: false,.
“implicit_payload_length”: 17,.
“implicit_crc_en”: false,.
“implicit_coderate”: 1
},
Set “spread_factor”: to 11 fix the problem

is this the same issue - https://forum.chirpstack.io/t/duplicate-downlinks-got-as-uplinks/8098 ?