Client crash random on Join a server after transfer

[Crasher508]

Version of Waterdog
This server is running Waterdog version git:Waterdog-Bootstrap:1.15-SNAPSHOT:9c87c52:6 by md_5

Expected Behavior
Client crash random on Join a server after transfer

Actual Behavior
The error just occurred two days ago without a change, I already asked for a solution on the Discord, unfortunately never received an answer

Crashdump, Backtrace or Other Files
https://youtu.be/ivJced8UNuo

Describe the bug
When transferring between two servers you are connected, but then sometimes everything hangs up and you are logged out of the proxy because of "Already connected to Proxy". There is a video in the appendix where it works randomly the first time and the bug occurs the second time

Server software used:
Pocketmine 3 (Altay)

[TobiasGrether]

The video doesn't show enough, what happened after you transferred the second time?

[Crasher508]

At the end of the video MC crashed and closed, at the end you can see Minecraft hanging up, then the recording was automatically stopped because the Minecraft application crashed and closed. I tested it with Android and Windows, you can also try it on the Bedrock server NoteLand.de 19132

[Crasher508]

Here is a Video from the Smartphone, on second transfer the MC crash too. https://youtu.be/uvFKGT-ngFA (My Smartphone isn't the best, thats the cause that I spawn in Dirt)