Hostnames cannot be resolved after upgrading to 22.04

After upgrading ubuntu from 21.10 to 22.04, my internet connection does not work anymore. I am connected to the WLAN and I can ping IP addresses (from the local network as well as from the internet) - however, resolving names does not work anymore. So ping 151.101.65.69 works with 0% packet loss but ping askubuntu.com gives me an error Name or service not known (it works from another machine that is connected to the same router).

When running nmcli, it shows the following DNS configuration:

DNS configuration:    servers: 192.168.17.1    domains: fritz.box    interface: wlp64s0

I also tried manually adding 8.8.8.8 to the DNS servers in the network manager (WiFi setting -> IPv4 -> DNS). Then, both servers are shown in the DNS configuration but the problem still persists.

Any idea what the reason could be, what I can do to narrow down the problem or how to solve it?