Yeelight RGB led bulb 2 can't connect to ZTE

Hello. I’ve bought this LED bulb. Every time I try to connect to my wifi router, it connects, but after that goes to 99% and show that Connection timed out. I’ve discovered, that it can’t connect only to ZTE routers. I’ve seen many people with that brand to complain. If I set up temporary hotspot with same name and password it will connect to it and after I turn it off, it will swtich to real router. But hotspot on laptop needs to be in NAT mode. Bridge mode won’t work. I think it’s something with obtaining IP address. In router I’ve set for my bulb static IP address, but still no luck connecting it. If I am succesfully connected to my router using hotspot technique, I can’t physically disconnect bulb from the electricity, or it will not connect anymore. So I think that there is some kind of issue with ZTE routers. Do you have any advice? Thanks

//edit:
I can ping my bulb, my router is only 2.4GHz and I can’t change my DNS server.

Could you see the bulb in router’s DHCP list when the connection is failed?

Hello. I can see bulb in DHCP list, I can also ping my bulb. There is I think problem, with contacting your cloud. I’ve tried pinging your AWS domains and it worked. I’m on Germany server.

Could you have a try with changing your router’s DNS server to 8.8.8.8 instead of using automatically allocation?

My router doesn’t allow changing DNS.

Please use another phone to setup a hotspots with 4G network and try connect the bulb to it to see if it works.

I can connect my bulb using hotspot, after turning off hotspot, it will reconnect to router and works. But if I reset my router or turn my bulb off, it won’t reconnect and I need to do it again.

If you can connect the bulb with hotspot, the bulb is ok. There must be some compatible problem between the bulb and your router. Which type is your router?

And why do you reset your router? Do you mean cut off power of the bulb and the bulb can’t reconnect again?

So you setup the same SSID and password of hotspot with your router, right?