productModel.js:

const mongoose = require("mongoose");
const productSchema = new mongoose.Schema({
  name: {
    type: String,
    required: true,//err here.
  },
})

There is an answer at link but those do not fix my error.

Here is the request that I send:
http://localhost:4000/api/v1/product/new (POST request with JSON content)
JSON:

{
    "name":"Vaseline petrolatum Jelly"
}

The above code gives the below error:
this.$__.validationError = new ValidationError(this);
^

ValidationError: Product validation failed: name: Path name is required.
at Document.invalidate (C:UsersDELLDownloadsreact-learnnode_modulesmongooselibdocument.js:3289:32)
at C:UsersDELLDownloadsreact-learnnode_modulesmongooselibdocument.js:3050:17
at C:UsersDELLDownloadsreact-learnnode_modulesmongooselibschemaType.js:1388:9
at process.processTicksAndRejections (node:internal/process/task_queues:77:11) {
errors: {
name: ValidatorError: Path name is required.
at validate (C:UsersDELLDownloadsreact-learnnode_modulesmongooselibschemaType.js:1385:13)
at SchemaType.doValidate (C:UsersDELLDownloadsreact-learnnode_modulesmongooselibschemaType.js:1369:7)
at C:UsersDELLDownloadsreact-learnnode_modulesmongooselibdocument.js:3042:18
at process.processTicksAndRejections (node:internal/process/task_queues:77:11) {
properties: {
validator: [Function (anonymous)],
message: ‘Path name is required.’,
type: ‘required’,
path: ‘name’,
fullPath: undefined,
value: undefined
},
kind: ‘required’,
path: ‘name’,
value: undefined,
reason: undefined,
[Symbol(mongoose#validatorError)]: true
}
},
_message: ‘Product validation failed’
}

I tried the solutions at link but none of them worked for me.