how to repair a wall thats falling down,,,, Can i save it

Your new brickwork looks fine, but it won't last. The concrete block wall behind has failed and is leaning forward under pressure from the ground behind, which has sunk to fill the void. There don't look to be any weepholes in the wall either, hence the damp. The whole thing really needs removing, a new decent foundation constructing, a new wall (with weepholes), heavy enough to resist the ground pressure, and backfilled with free draining material before repaving.
Yes it will cost the client, but what you have done is only a short term fix.

Won't break the land speed record !!

Loads will take the piss and say crappy stuff, but at the end of the day, your repair looks good and if customer is happy and you got some work then all is good.

wouldnt worry baut it mate leaning tower pisstaaa never fell...your job was good...

Good job

Great stuff! 🍻🍻🍻🍻

Its a shame your client didnt want it done properly, you pay peanuts you get monkeys.