Your layer is m-aware. If you are editing the web feature layer through REST or SOAP endpoints, you will be unable to edit feature geometry unless you supply an m-value with the edit.
- Do nothing. You should be fine if you will not be editing feature geometry, or if you will be editing but supplying m-values with the edits.
- Alternatively, you can remove the layer from your map if it is not needed.
If you have data that has m-values, these features can be deleted, new features can be inserted, and the attributes of existing features can be edited but the geometry cannot be edited. All new features will have their m-values set to NaN when inserted through the REST and SOAP endpoints. If features with m-values are edited through the web feature layer in ArcGIS Pro with the local editing commands, all editing operations are supported.