How to redo my sinking border blocks? They were level when I bought ho

I would take them all up use a claw tool and work the ground the weather afyer so long you have to redo this and it will be nice again😎

Pick them up and level the ground underneath, make sure it is packed down well and replace the border.

pick them up ,use paver base ,place down and pack in sand

I rake the area, then broadcast DRY sakrete to the proper grade , lightly shower with a hose ,then replace the pavers,ideally a couple inches of cement mix will last much longer than the sand mix , broom into the joints clean /play sand

The soil has either sunk or washed away. Remove the blocks, level the soil, tamp it down well, replace the block.

William is right about the reason why the blocks have shifted. Randy is right about using a substance stronger than sand to pack the blocks in position. The ground underneath the blocks should be dug down and then reinforced at least the same depth as the height of the blocks above ground. I would suggest using crush, or for a longer lasting job, as he suggested, cement mix. Use a level tool though to ensure that the blocks are really level, don't just eyeball it, as once the cement starts to set, you will be stuck! with where the blocks are.

Thanks for helpful ideas