Region : Czech Republic

Model : TL-WA850RE

Hardware Version : V1.2

Firmware Version :

ISP :

Hi!
I can't seem to solve this issue. I bought TL-WA850RE about half a year ago and everything was working perfectly until last week when I changed wi-fi password on the main router. Of course I changed the settings in the range extender too and then restarted all the devices, but now I can access internet only when I am wired to the range extender via cable. If I connect using wireless, it says I have limited connection and can't access internet nor main router nor range extender administration pages. In Windows it also says the network is public instead of private and is named "Unidentified network" instead of the name of my network.
This problem appears only on my laptop, when I try to connect with other 2 laptops we have at home, there is no problem.
I checked the connection and it obtains the IP address, DNS, gateway etc. correctly, but there is simply no connection and when I try the Windows diagnostic tool, it says it can't reach the default gateway.

Here are couple of solutions I've tried, but haven't worked:
- manually deleting the wifi profile from Windows
- changing the password back to the old one
- changing wifi channel
- changing to static IP / turning off DHCP
- updating the firmware to the newest one

Any ideas? I would be grateful for any help. Thanks.