I know this is a very cliche subject, but I feel I’m missing something simple.
This is the DB:

{
 "_id" : "66846180e4d8e74d393f4c57",
 "name": "GB",
 "locations": [
  {"name": "GB01", "dateTime": ""},
  {"name": "GB02", "dateTime": ""},
  {"name": "GB03", "dateTime": ""},
  {"name": "GB04", "dateTime": ""},
  {"name": "GB04", "dateTime": ""},
  {"name": "GB05", "dateTime": ""},
  {"name": "GB06", "dateTime": ""},
  {"name": "GB07", "dateTime": ""}
 ]
}

and this is the query:

const result = await Lakes.updateOne(
 {
  _id:"66846180e4d8e74d393f4c57"
 },
 { $set: { "name":name, "locations.$[elem].dateTime": "new dateTime" } },
 {
  arrayFilters: [
   { "elem.name": "GB01" },
  ],
 }
)

I know the lookup is finding the document, I added the $set for the name to test and it’s updated – I just can’t get the arrayFilters to work. I even normalized the data to simplify the query, but I’m getting no where…If anyone can point out my mistake I’d be very grateful…