How to fix uneven pavers?

[upgrades]

Photo 1 Photo 2 

Photo 3

I've got 2 areas with pavers (shown in the first photo) in the garden.
To the left of the photo 1, area 1 has two levels of pavers and they sit on top each other n no movement and wobbliness.

Second area, at the top right of photo 1, where single level of pavers r laid on top of concrete (by the looks of it) as shown in photo 2 n 3. Second area's pavers no longer bonded with the concrete and they wobble, sometimes if not put properly, they fall forward or backward. What's the best way for area 2's pavers to sit tight on the concrete? Would like them to be strong and stable enough with the human traffic. Appreicated.

[EricL]

Hello @upgrades 

I propose washing the pavers and the concrete base with water and detergent in combination with a bristle brush to remove any mould or mildew on the top and bottom surfaces. Once the paver and the concrete base are dry, I suggest using Dingo 10kg Mortar Mix along with a Craftright 250mm Brick Trowel to place a thick spread of mortar on the concrete base for a solid connection between the two surfaces. My best advice is to give the mortar enough time to fully cure before attempting to put anything on top of the paver.

Let me call on our experienced members @Dave-1 and @Nailbag for their recommendations.

If you have any other questions we can help with, please let us know.

Eric

[upgrades]

Thanks @EricL. Helpful as always.

Confirming the steps:
1) washing the pavers and the concrete base with water and detergent in combination with a bristle brush to remove any mould or mildew on the top and bottom surfaces,

2) Once the paver and the concrete base are dry, using Dingo 10kg Mortar Mix along with a Craftright 250mm Brick Trowel to place a thick spread of mortar on the concrete base and lay pavers,

3) give the mortar enough time to fully cure before attempting to put anything on top of the paver.

[EricL]

Hi @upgrades 

Yes, those are the general steps to attach the pavers to the cement base. My best advice is to mix the mortar in a thick consistency and not to add too much water to prevent it from turning into slurry.

Eric

[Dave-1]

Good Evening @upgrades 

Looks like the old mortar has broken away and shifted over time (if it was there in the first place) Re-mortaring would be the steps I would also take. 

I also would step through the same ones @EricL has suggested.

Dave