Is this a settling problem?
Was there Proper drainage? Looks like erosion . Or Past owner weighed 800 Lbs.
Agree looks like erosion.
Curious also there is no expansion joint at that location…
This would include a junction of sidewalks, sidewalk with a driveway, building, curb, or other similar members, as well as where a floor slab joins a column, staircase, etc. An expansion joint should always be utilized where a concrete member will join or abut an existing structure of any type. Normally, expansion joints are not provided in sidewalks other than where the walk abuts an existing structure. The square formed by the intersection of two sidewalks should have pre-molded expansion material enclosing the perimeter.
looks like a poor concrete job to me…If you look you can see the form marks on both sides and if this is against or part of the stemwall they forgot to complete
the concrete footing behind it…Unless Im seeing things…What is above that???