Im playing Silent Gear on version 0.6.7 at 1.12.2 and i made a pickaxe with a diamond,a emerald, and a crimson steel, some time the pickaxe starts to insta mine stones in the map but dont really break them, and this is happening in a high frequency

Someone can help me to solve this?

No idea if that's something I can fix or not. Either way, 1.12.2 is no longer supported.