Reactjs – UnhandledPromiseRejectionWarning: CastError: Cast to Number failed for value "[email protected]" (type string) at path "mobile" for model "users"

const express = require('express');
const app = express();
const Register = require('./model/register')
require('./db/conection');
app.use(express.json());

app.get('/' , async(req,res)=>{
    res.send("hello")
    
})
app.get('/search/:key',async(req,res)=>{
    let sKey=req.params.key;
    console.log(typeof(sKey));
    let searchData=await Register.findOne({'$or':[
        {name:sKey},
        {email:sKey},
        {address:sKey},
        {mobile:sKey}
    ]})
    res.send(searchData);
})
app.listen(5000,()=>{
    console.log("server start");
    console.log(`http://localhost:5000`)

});

I am triying to create searching api for getting detail of a particular user by email or mobile number and my code shows this error :UnhandledPromiseRejectionWarning: CastError: Cast to Number failed for value "[email protected]" (type string) at path "mobile" for model "users".

my model file is –

const mongoose = require('mongoose')
//const {Schema} = mongoose
const registerSchema = new mongoose.Schema ({
name:String,
email:String,
address:String,
mobile:Number,
password:String,
date:{type:Date , default:Date.now}
});
const Register = mongoose.model('users',registerSchema);
module.exports= Register;