Z2M - can not pair Xiaomi Human Body Sensor

First of all, a huge thank you for the Zigbee2MQTT project!
I started today, it was easy to set up and get going. Fantastic.

After pairing a few devices I am stuck on this one, a Xiaomi Motion Sensor (RTCGQ01LM I think).
I have one paired successfully but the next one gives me this issue:

Jun 04 15:51:37 GatePi npm[1022]:   zigbee2mqtt:debug 6/4/2019, 3:51:37 PM Received zigbee message of type 'endDeviceAnnce' with data '"0x00158d00014dd511"' of device 'undefined' (0x00158d00014dd511) of endpoint 1
Jun 04 15:51:37 GatePi npm[1022]:   zigbee2mqtt:warn 6/4/2019, 3:51:37 PM Device with modelID 'undefined' is not supported.
Jun 04 15:51:37 GatePi npm[1022]:   zigbee2mqtt:warn 6/4/2019, 3:51:37 PM Please see: https://www.zigbee2mqtt.io/how_tos/how_to_support_new_devices.html

ModelID : undefined

I tried to pair it back to the Xiaomi Gateway, that was no problem, I tried to update it but there seems not to be such an option.

Any idea how to debug from here?

thanks

some more info, I think this is the relevant entry in the database.db

{
	"id": 6,
	"type": "EndDevice",
	"ieeeAddr": "0x00158d00014dd511",
	"nwkAddr": 6891,
	"manufId": 4151,
	"epList": [1],
	"status": "offline",
	"joinTime": null,
	"endpoints": {
		"1": {
			"profId": 260,
			"epId": 1,
			"devId": 260,
			"inClusterList": [0, 3, 25, 65535],
			"outClusterList": [0, 3, 4, 5, 6, 8, 25],
			"clusters": {
				"genBasic": {
					"dir": {
						"value": 3
					},
					"attrs": {}
				},
				"genIdentify": {
					"dir": {
						"value": 3
					},
					"attrs": {}
				},
				"genGroups": {
					"dir": {
						"value": 2
					},
					"attrs": {}
				},
				"genScenes": {
					"dir": {
						"value": 2
					},
					"attrs": {}
				},
				"genOnOff": {
					"dir": {
						"value": 2
					},
					"attrs": {}
				},
				"genLevelCtrl": {
					"dir": {
						"value": 2
					},
					"attrs": {}
				},
				"genOta": {
					"dir": {
						"value": 3
					},
					"attrs": {}
				},
				"manuSpecificCluster": {
					"dir": {
						"value": 1
					},
					"attrs": {}
				}
			}
		}

and this line is missing

"modelId": "lumi.sensor_motion",

As suggested on the discord chat, I just kept pairing and pairing and at some point it worked.