Updating hosted layer doesn't work when referencing a different map

[AlfredBaldenweck]

Hi all,

I'm trying to automate updating a hosted layer.

arcpy.AddMessage("Beginning to update the web layers.")

aprx = arcpy.mp.ArcGISProject("CURRENT")
mapL= aprx.listMaps("Map")[0]

ahulay= mapL.listLayers("Ahupuaa_NAD83_PA11")[0]
mokulay= mapL.listLayers("Moku_NAD83_PA11")[0]
tmklay= mapL.listLayers("HawaiiCountyTMK_NAD83_PA11")[0]

draft= mapL.getWebLayerSharingDraft('HOSTING_SERVER',
                                    'FEATURE', 
                                    'KMS_File_Index', 
                                    [ahulay, mokulay, tmklay]) 
# Change its properties to allow it to Overwrite the existing layers.
draft.overwriteExistingService = True

draftaddress = r"K:\...File_Index.sddraft"

arcpy.AddMessage("Prepping to share as a weblayer")

draft.exportToSDDraft(draftaddress)
arcpy.server.StageService(draftaddress, 'KMS_File_Index.sd')

arcpy.AddMessage("Uploading weblayer")
arcpy.server.UploadServiceDefinition(r'KMS_File_Index.sd', 'HOSTING_SERVER')

arcpy.AddMessage("Successfully updated the KMS web layers.")

It works fine when  mapL is set to "Map" (Line 4), but when I added those same layers to a a new map (and saved) , then replace "Map" with the new name, it will run all the way through with no problems, but the updated web layer won't have anything in it 

The only change I'm making to the code is the value in mapL. I'm not getting any index errors, so I 'm sure that everything else is right. Does anyone have any ideas as to how to fix this?

Thanks!