Join request accept reply sent on wrong frequency

I spun up Chirpstack container on a laptop to use with the Heltec HT-M01 gateway. Mostly likely due to a configuration error on my part, the reply to the OTAA join request reply is being sent on 902.3MHz, the same frequency it was received on, instead of 923.3MHz. I can see this both on an SDR and in the JSON that’s sent to the packet forwarder driving the HT-M01. I have a Chirpstack container on another machine that’s connected to a Multitech gateway, and that works perfectly.

I created the gateway, application, and devices profiles to match the first container. I’m using US 915 sub-band 1, but nowhere in the web UI do I see where the downlink frequency is specified, nor how it’s derived.

What would I have missed or have set wrong that would cause the join request reply to be sent on 902.3MHz instead of 923.3MHz? The only difference is the Heltec is using their picoGW-packet-forwarder, whereas the Multitech has it built in. There’s nothing in the global_conf.json file that pertains to the downlink, and the one on the Multitech is fundamentally the same as the Heltec configuration.

Any ideas? Thanks!

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