This issue is not reproducible with the ArcGIS Runtime SDK for iOS version 100.5 with the following sample: https://github.com/Esri/arcgis-runtime-samples-ios/tree/a0efcf50a37c086c543b69ce0ee639783427ecae/arcgis-ios-sdk-samples/Maps/Display%20device%20location
If you are still experiencing this issue, please reach out to Esri Support Services.