Remote AT command request not working

My setup looks like this: 1 coordinator, 2 routers in the same network. All of them are 865/868LP 10K devices.

I’m trying to query the AT parameter DB (RSSI) from one of the routers through the coordinator device. All devices are in API1 mode. The coordinator is connected to XCTU. To query the parameter, I use the following frame:
Query: 7E 00 0F 17 01 00 13 A2 00 40 99 43 80 FF FE 02 44 42 11

00 13 A2 00 40 99 43 80 is the MAC address of the router I’m interested in. I have checked and verified that this is the correct MAC address.
However, the above query always returns a 0x97 frame with “TX failure” in XCTU which looks like this:
Response: 7E 00 0F 97 01 00 00 00 00 00 00 FF FF FF FE 44 42 04 E2

It takes about 6 to 8 seconds for this reply to be received in XCTU. I even receive this reply with both routers powered down.

When I send the same frame, but with the MAC address set to broadcast, both routers reply as expected. This frame looks like this:
Query: 7E 00 0F 17 01 00 00 00 00 00 00 FF FF FF FE 02 44 42 64

Response 1: 7E 00 10 97 01 00 13 A2 00 40 93 1B 85 FF FE 44 42 00 36 86
Response 2: 7E 00 10 97 01 00 13 A2 00 40 99 43 80 FF FE 44 42 00 38 5B

This works exactly as expected, but I don’t want to use broadcast. I ONLY want to address a single device. Why won’t the first query work??? Querying different parameters give the same error.

Are you able to exchange Tx_Req data packets between coordinator and Routers on individual basis?

Yes, I am. Both of my routers are sending TX request packages to the coordinator (by sending it to the actual MAC of the coordinator) and they come in just fine.

may be your routers are placed just at the edge of network. Try put them closer to Coordinator and it should work fine.

My routers are sitting on my desk, half a meter apart. Distance shouldn’t be an issue. When doing a range test in XCTU, I get 0% packet loss (100 packets).