Describe the bug
When I have these three plugins installed (see below) when mining with a 3x3 pickaxe, sometimes when mining nothing will break except one block in the corner of the 3x3 pattern. Essentially, picture a 3x3 grid. You mine in the middle with a 3x3 pick, all of it should break, but occasionally, only a random corner of the 3x3 grid will break. This ONLY happens when ProtocolLib is installed with Spartan. When I run Spartan and AdvancedMiningTools it runs fine. When I run ProtocolLib and AdvancedMiningTools it's fine.

ProtocolLib: (https://www.spigotmc.org/resources/protocollib.1997/)
AdvancedMiningTools: (https://www.spigotmc.org/resources/advancedminingtools-mining-tools-1-8-1-16.91437/)
Spartan: (https://www.spigotmc.org/resources/spartan-anti-cheat-advanced-cheat-detection-hack-blocker-1-7-2-1-16-5.25638/)

To Reproduce
Steps to reproduce the behavior:

1. Install all three plugins listed above.
2. /amt give username shockwave 3 1
3. Mine with it until it happens. (Looking straight down and mining a grass block seems to make it more common than regular mining)

Expected behavior
Upon mining, you should have dug 9 blocks in total in a 3x3 grid.

Screenshots
If applicable, add screenshots to help explain your problem.
What should happen:
What occasionally happens:

Version Info
https://pastebin.com/Gynh6xmU

Additional context
Please keep in mind that this happens occasionally. But it's still very common to the point that it is very concerning and annoying. I tried contacting the Dev of Spartan but he says that I should contact ProtocolLib because he's not reliable for it. I am in contact with AMT (AdvancedMiningTools) dev all the time and he has tried his best to work around all of this but he can't seem to figure out why this is happening.