Sometimes Ipv6 gets in the way of ipv4/ipv3 prodicals, When The undying connection is worn, it relys on ipv6 but when its badly worn as so peer-to-peer WILL NOT WORK.(Thus Causing Blockland to not work on internet) So when its had some time to recover. It'll be ready for another 3 mounths Of full-time use. But really Its best to turn this off for awhile to resolve this issue, Trust me this has been Proven Countless times to work.
Note: Ipv6 Has been known to get in the way of ipv4 funcations, if its worn.
^On Topic Edit^