Post the output:
resolvectl dns; resolvectl domain; \
grep -e ^hosts: /etc/nsswitch.conf; \
grep -v -e ^# -e ^$ /etc/resolv.conf
Try to enable DNS encryption:
sudo mkdir -p /etc/systemd/resolved.conf.d
sudo tee /etc/systemd/resolved.conf.d/00-custom.conf << EOF > /dev/null
[Resolve]
DNSOverTLS=yes
EOF
sudo systemctl restart systemd-resolved.service