There are few things I usually do when installing linux. One of them is disabling ipv6. If you also feel like to disable but not sure how, here is what I did.
First, add below to grub for starting kernel, and remember to run grub-mkconfig.
Second, update the dhcp config file (/etc/dhcpcd.conf) with below.
Reboot and try.
without updating dhcpcd config file would sometimes work, depends on the server that you connect to. I sometimes run into the problem that the dhcp server sending ipv6 info to me when initializing thewifi connection.