help loose edging blocks

[moore005004]

Hi,

I am a total novice I layed some garden border edging blocks 3 weeks ago, I dug a 10" trench leveled it and tampered it down poured dry concrete in the trench leveled that, set the blocks in tapped them in and leveled them off (forgot to mention the blocks are 8"x 5"x 2") I then sprayed them with water. Problem is the blocks haven't stuck you can just lift them up the concrete base is fine and sound and fully cured but the blocks are loose how can I secure the blocks so they don't move? I have attached a few pics showing edging and how blocks lift up please give feedback thank you. I'm from the UK

https://photos.google.com/photo/AF1QipM0HSCkUr69WP8z2igDoVsvvSdUmd2R6_o_SPva
https://photos.google.com/photo/AF1QipPnTXV3xKLYxqdDkVrcQQiIXZHd3MA_CW9H01nv

 

[sxturbo]

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