CosmosDB migration MERN-Can't read collections

I'm exporting a database from mlabs to CosmosDb.

after failing with other methods, I finally exported via mongodump and imported into CosmosDb. I can read the collections in studio 3t.

but when connecting in Express/mongoose via the connectionString, the collections all return [].

I've added my IP to the firewall.

It's not the code, when I point back to the mlab db everything retrieves correctly.

what am I missing in CosmosDb?

using:
"mongodb": "^3.0.4",
"mongoose": "^5.0.6",

router.get('/',function(req,res,next){
var ret={};
var query={"businessCode" : 'Travis'};//req.decoded.businessCode};
var cursor=db.collection('lookup').find(query).toArray(function(err,items){
if (err){
next (err);
} else {
//items = [] ...should definately return a collection
console.log ('****** items', items);
}
})
});