I'm getting the following error in my server sponge forge with the Stoneblock 2 v1.3.0 modpack
It happens suddenly when a user connects, unfortunately I can not identify who it is, since the crashreport does not provide the location of the block that is hanging.

fluxnetworks-1.12.2-3.0.19-21.jar
sonarcore-1.12.2-5.0.19-20.jar
spongeforge-1.12.2-2768-7.1.5-RC3526.jar
Forge 14.23.5.2796

CrashReport: https://pastebin.com/raw/VAURbkHm
Log: debug-1.log

Fixed: This shouldn't occur in next version as this loop shouldn't continue indefinitely. Thanks to @BloCamLimb