Unable to move features when editing a feature service in ArcGIS Online

Description

When editing an existing feature in the ArcGIS Online Map Viewer it is not possible to move a point or the vertices of the feature, even when full editing control is enabled.

Cause

This is expected behavior in ArcGIS Online. Feature services that have m-values enabled do not allow editing of the geometry of existing features. It is possible to add, delete, and edit the attributes of m-value enabled features, however the features cannot be moved spatially.

Solution or Workaround

To edit the geometry of a feature service in ArcGIS Online, m-values must be disabled in the service properties. To remove m-values from an existing feature service, the source data should be altered and the service republished or overwritten.

1. In ArcMap run the Feature Class to Feature Class tool, using the Environment Setting for Output has M Values set to disabled. This copies the features to a new feature class in a file geodatabase. Refer to the following workflow for more details: How To: Remove Z- and/or M-values from a feature class.
2. Once the m-values have been removed from the source data, republish or overwrite the existing service so that users can move the points.

Note:
To edit geometry for existing features in the layer, the layer owner must move the data with m-values to a separate layer (which can be in the same service).

Note: 
A polygon feature on top of a point feature in the web map will also prevent moving points. Turn off any polygon layers that are above the point layer in the table of contents, then points that were previously beneath polygons can be moved.