I got this issue: ChaoticTrials/SimplyTools#9
As mentioned in this issue, the problem is caused by HT's TreeChop. This happens because the BreakEvent gets canceled because of this PreChopEvent cancelation:

This results in only breaking one block when breaking. Here you can see my implementation for breaking more than one block: https://github.com/MelanX/SimplyTools/blob/15225940638c03503fb1476294d5eeae53b68ba5/src/main/java/de/melanx/simplytools/util/BlockBreaker.java#L23-L38

Setting multiMine config to false fixes the problem.

Probably related to #214

Thanks for reporting! Right, the line you pointed out is breaking everyone's AOE tools. I got all excited about finally fixing a Multi Mine-related bug and didn't think hard enough about the side effects. I'll post a fix as soon as I can.

This should be fixed in 0.18.4, but I'll leave this issue open til I can confirm