Esri_runtimecore::Common::Null_ptr_exception: Null pointer

[AfrozAlam]

I have created an iOS app using ArcScene and displaying 3D images with extruded buildings. I am using navigation control. When I close the ViewController and Go Back then following error occured.

Esri_runtimecore::Common::Null_ptr_exception: Null pointer

I am sharing the Code, Screenshots.  Can anybody help me to get rid of this.

regards,

Afroz

[Nicholas-Furness · Accepted solution]

Do you get the same error if you skip the elevation source? https://alkhazna.gisqatar.org.qa/server/rest/services/CGISRASTER/QATAR_2021_09_C050_PLE/ImageServer is not accessible to me to test against.