So it looks like your adapter is assigned an IPv6 address, as seen here:
inet6 fe80::9f7c:98f5:e6b4:e23a/64 scope link noprefixroute
I had a look online for some answers, particularly this last line was of interest:
valid_lft forever preferred_lft forever
(I hadn't known about this before, this post describes what they mean - turns out my WLAN also has the same but mine has an inetline too since it has an IPv4 address)
This answer might be worth a try:
Apparently it could be down to a race condition during boot. Try adding:
auto enp3s0f1
to /etc/network/interfaces and reboot.
Alternately, if that doesn't work and your network doesn't need IPv6, you could open Network Manager ( 
→ Edit Connections) and disable IPv6 (Set to "Ignore"). Maybe check your IPv4 settings and set them to static addresses if you're familiar with networking.