EU868 channel mask ack message

[Net-Metrics]

1. Are you using Helium hosted Console or running your own open source Console? Nova

2. If you are on Helium hosted Console, which url are you currently on? https://console-vip.helium.com/

3. If you are experiencing bugs in Helium hosted Console, please specify your Organization name and Device ID (ex. 3483050b-284d-47e2-8eda-e087fc03a753).

8bd91ec2-bee2-4d26-8848-d5edd221f225

Please describe your issue:

Several of my devices (with ADR enabled) are stuck in a loop whereby console sends a downlink after every uplink because my devices do not send a channel mask ack.

I can see the following in the downlink, channel mask is set to 255

category	"downlink"
data	
devaddr	"64080048"
fcnt	21
hotspot	{…}
integration	{…}
mac	
0	
channel_mask	255
channel_mask_control	0
command	"link_adr_req"
data_rate	5
number_of_transmissions	0
tx_power

And I get the following in the next uplink

category	"uplink"
data	
dc	{…}
devaddr	"64080048"
fcnt	40
hold_time	0
hotspot	{…}
mac	
0	
channel_mask_ack	0
command	"link_adr_ans"
data_rate_ack	1
power_ack 1

I'm in EU868 if that makes any difference. Device downlinks are received, and the ack for data_rate & power get sent OK every time