PS4 users in the UK are having problems connecting to the PSN because of the heavy traffic that Sony is experiencing shortly after the PS4 launch. Some users have even reported getting kicked off the PSN after successfully connecting as well. Many of you may remember similar problems after the PS4 launched in the U.S. earlier in November, but the UK’s launch was so severely borked that Sony had to take action. As a result, the company has disabled the “redeem voucher” functionality of the PSN to try and make the service operate more smoothly. They also disabled the What’s New and Content Information screens in European territories.
This has annoyed several gamers who cannot update their PS4 due to the network outage. Luckily, Sony does support offline firmware updates. Simply go to the official Sony firmware update site , download your new firmware onto a USB stick, and stick it into your PS4 to allow the update to proceed as normal. In fact, we suggest doing this as updating through your console will just increase the traffic that Sony is experiencing.
Source: PS4 Twitter