Advice needed on rendering work

Hi all. Looking for advice as to what to do re a newly rendered garden wall. The wall is constructed of concrete blocks with block paving to the rear elevation and the garden to the other.



I appointed a contractor to render the wall (front and rear elevations and across the top) in Monocouche render after having found him on one of the 'trusted' websites' where he had over 30 'recommendations'



I'm concerned about the finished job (note - despite my best DIY attempts I am not and will...

Advice needed on rendering work