Firebase reference typedata goes wrong to be array (Retool)

Question

When I tried to add a Reference datatype to my Firebase db in Retool on raw mode, the trouble is coming out that. the reference datatype is stored as a array Here is my code

const data = {
   User: { $ref:"User/LjHVAMlm0yY3o5tktIkZ00aN0oC2" },
   }

db.firestore().collection('Ticket').doc().set(data);

Is it any solution? Thanks!

I have tried the solution on this post

{ 
const data = {
   myRef: {"$ref": "coll_2/doc_1"},
   }

db.firestore().collection('Ticket').doc().set(data);
}

The wrong array datatype is also coming out too. enter image description here enter image description here