Block paving has started pitting

I'm not sure with out seeing the job, but by the sound of it, it looks like the foundation is not strong enough and preparation has not been done to the standard of the block paving driveway system.

Hi gem, without actually seeing your driveway it’s hard to be 100% positive, however the most common reason for Block paving driveways to be dipping in areas is foundation and preparation of the driveway has not been done correctly. You want 200mm - 250mm of hardcore sub base type 1 compacted. Also the screeding and compacting of the sharp sand is also very important if this is too thick then it won’t compact properly, and if this is not compacted and screeded correctly that could also be causing dips on your driveway. The edging will be any of the reasons listed above or it’s not correctly haunched with concrete holding it in which will allow movement on edges.

I would say without seeing the driveway, that the sub-base is insufficient! The driveway for a domestic dwelling should be no less than 300-350mm excavated all over. I would probably say that the sharp sand screed is possibly to deep.

Bad Bach blocks delivers to job happens quite a lot . Called seconds materials bad suppliers

This could be due to a poor batch of pavers as we all know blockpavers are made of concrete is the batch is weak this will cause this to happen

This sounds like a bad batch of Block from manufacturers, sometimes air bubbles inside the block when made can cause superficial damage at a later date