Date & Time: Since March 15th
ISP: Kyläverkko - yok.fi /FUNET CSC
Type of Internet Connection: WAN/Ethernet, Fibre
Internet Connection Speed: 1Gbit/s / 1Gbit/s
Frequency: Always
World name: All worlds and all datacenters

Steps:
1. When selecting either start to get to the character selection, or swapping datacenter, it after a brief moment gives the 2002 error and closes the game.

Connection Specs
- Type of internet connection/provider: Kyläverkko administred by yok.fi, part of FUNET but CSC
- Modem maker/model number: RT-AX86U

Ever since 15.3 I've been unable to connect to the game at all using my normal network. I've only been able to connect with either mobile internet or while using the Cloudflare WARP software, and sometimes it will work with a VPN. These however affect the network speed and latency.
I've heard from other people in the area that they are having this exact same issue. My ISP/Network administrators have confirmed they can replicate the issue on the network. So the issue is not local system related. They have also confirmed they made no changes to the network at the time the issues started, or that there should be anything blocking the connection. They also managed to replicate the issue using a separate campus network that is also part of FUNET. They were then further in contact with the administrators to FUNET that confirmed that there had been no changes and that they were not blocking anything.

My ISP concluded that they could only really guess where the issues might be. Their guesses were that either SE is somehow blocking the network or that there is an issue with the routing to the game. They reported doing their own tracert and the hops that seemed odd/weird to them were hops on/between hops on the NTT network or ones just prior to the hop to the actual lobby/world servers. According to them all the traffic goes/was going through 204.2.229.238 which they found odd as well as that hop only responding every second time. They also reported that for them while 204.2.229.230 did respond the previous hop kept changing. When I run a tracert I can however not see a hop via .238 so with that I'm just reporting what my ISP mentiond.

Below is the excerpts from the tracert my ISP did and that they shared with me relating to the issues.

$ traceroute 204.2.229.106
1
2
.
.
18 ae-1.a00.snjsca04.us.bb.gin.ntt.net (129.250.2.228) 183.217 ms 183.104 ms 167.733 ms
19 xe-0-0-42-1.a00.snjsca04.us.ce.gin.ntt.net (192.80.16.69) 169.926 ms 169.867 ms 170.893 ms
20 * * *

$ traceroute 204.2.229.106
1
2
.
.
18 ae-1.a00.snjsca04.us.bb.gin.ntt.net (129.250.2.228) 167.827 ms 165.591 ms 164.709 ms
19 xe-0-0-42-1.a00.snjsca04.us.ce.gin.ntt.net (192.80.16.69) 171.376 ms 168.456 ms 168.182 ms
20 204.2.229.238 (204.2.229.238) 172.492 ms * *
21 * * *

- - -

$ traceroute 204.2.229.11
1
2
.
.
18 ae-1.a00.snjsca04.us.bb.gin.ntt.net (129.250.2.228) 171.186 ms 171.150 ms 171.114 ms
19 xe-0-0-42-1.a00.snjsca04.us.ce.gin.ntt.net (192.80.16.69) 172.631 ms 172.244 ms 167.654 ms
20 204.2.229.238 (204.2.229.238) 170.990 ms * 168.056 ms
21 * * *

$ traceroute 204.2.229.11
1
2
.
.
18 ae-1.a00.snjsca04.us.bb.gin.ntt.net (129.250.2.228) 164.798 ms 166.018 ms 164.725 ms
19 xe-0-0-42-1.a00.snjsca04.us.ce.gin.ntt.net (192.80.16.69) 169.145 ms 171.963 ms 171.927 ms
20 * * *

- - -

$ traceroute 204.2.229.230
1
2
.
.
18 ae-1.a00.snjsca04.us.bb.gin.ntt.net (129.250.2.228) 170.799 ms 170.728 ms 170.688 ms
19 xe-0-0-42-1.a00.snjsca04.us.ce.gin.ntt.net (192.80.16.69) 174.755 ms 169.658 ms 170.820 ms
20 204.2.229.249 (204.2.229.249) 172.827 ms 167.965 ms 204.2.229.245 (204.2.229.245) 167.926 ms
21 204.2.229.230 (204.2.229.230) 169.313 ms 169.749 ms 169.967 ms

$ traceroute 204.2.229.230
1
2
.
.
18 ae-1.a00.snjsca04.us.bb.gin.ntt.net (129.250.2.228) 168.177 ms 168.969 ms 168.053 ms
19 xe-0-0-42-1.a00.snjsca04.us.ce.gin.ntt.net (192.80.16.69) 171.677 ms 169.423 ms 169.652 ms
20 204.2.229.245 (204.2.229.245) 168.224 ms 204.2.229.249 (204.2.229.249) 171.216 ms 168.659 ms
21 204.2.229.230 (204.2.229.230) 167.374 ms 167.849 ms 168.211 ms

- - -