mDot data not received by mTech gateway

hi Andrew!,
i tried that, but is already enabled,

/var/config/lora/global_conf.json
"radio_1": {
"enable": true,
"type": "SX1257",
"freq": 868500000,
"rssi_offset": -166.0,
"tx_enable": false
},

what else could be the problem? thanks!