Okay, so that’s
05 03D2AD84 = RXParamSetupReq + 4 bytes of details
03 55 FF00 01 = LinkADRReq with
DataRate_TXPower = 0x55
Which (assuming EU868) looks like it’s commanding SF7 / 125 kHz
So the question seems to be: why is your node not receiving, or not honoring this?
One possibility is that the fixed frequency of 869.525 and SF12 suggest all of these are being sent with RX2 settings, yet the time delay seems to be only one second, which sounds more like RX1. Can you compare the actual gateway timestamps for TX and RX and see if they differ by 1 million uS or 2 million?
I’m not really familiar with the EU868 regional specs but it appears that RX1 should be on the same frequency as the uplink.
Perhaps you can figure out if:
The node does not properly implement RX2
The network is somehow sending mixed up TX requests, ie, RX2 frequency at RX1 timing
Additionally, SF12 is LoRaWAN RX2 settings - TTN EU868 does not use that, but a non-standard SF9.
Note that The Things Network uses the non-standard SF9BW125 data rate for RX2 in Europe.
So if the above replies at SF12BW125 on 869.525 irrespective of uplink frequency are being commanded by a TTN server, to my unfamiliar eye it would seem that server is a bit… confused.
Perhaps someone more familiar with everyday operations in Europe can chime in and offer a better of explanation of what is wrong (or perhaps not actually wrong)