Connection problems multiple lamps


I’ve have problems connecting my lamps to a new bridge.

I’ve been through a lot of advices (Google and this page), but nothing seems to work.

The lamp is outside and the bridge on the other side of the wall; approx. 2m distance.
No matter how I try to connect it can’t find the lamp. I’ve tried using the SN, changing the ZigBee channel, held the bridge out window so there’s a direct line of sight etc. nothing helps. I’ve also scanned the 2.4 GHz channel using my WIFI and it’s only around 17-20% utilized with very to none interferance.

The lamp is the one closest to the bridge; there’s multiple lamps outside, only one is found.

Is it possible to do a reset of the lamp? Can I configure the lamp and bridge to use a specific Zigbee Channel?

Any advice appriciated.

BR Ronni