This is not every time so may be hard to reproduce, when becon mining to remove a small mountain, with haste 2 efficiency 5 netherite pick on my BDS world, I noted that I had an issue picking up stacks of blocks from my inventory when I was trying to offload to free up space, logging off and on again didn’t help, these stacks of stone and cobblestone were not full stacks yet the stopped even adding blocks when I mined more of the same, instead the new blocks would create a new stack and I was left with locked and unusable inventory slots, the only way I could resolve this was to pickblock on the same stone on the ground, this then transferred the locked stacks to my hot bar and allowed them to be moveable again. I had this glitch 4 times in a 20 minute window.

However, my becon was only half in range so I was running in to range to get the haste 2 effect to mine the spots furthest away.