Redis OM fetchRepository error using typescript

I am building a shopping cart using expressjs, typescript and redis OM as the in memory database. After creating a schema using Redis OM, an error

Property 'fetchRepository' does not exist on type 'typeof App'.ts(2339)

in this line of code

export let CartRepository = client.fetchRepository(CartSchema)

I am a bit new to typescript

the whole schema:

import { Entity, Schema,Repository } from 'redis-om'

import client from '../../../../app'

export default class Cart extends Entity {}

const CartSchema = new Schema(Cart, {
  item_name: { type: 'string' },
  item_Cost:{ type: 'number' },
  coin_type:{type:'string'}
})

export let CartRepository = client.fetchRepository(CartSchema)

CartRepository.createIndex()

Below is where the client is being exported from .

//app.ts
 const url:any = process.env.REDIS_URL

        const connection:any =  createClient({url}).connect().then(() =>{
            console.log("database connected successfully");

        })
        let client:any;

 module.exports.client =  new Client().use(connection);