Use map instance outside onLoad in react-google-maps - google-maps

Question

I am trying to use places library, It requires map instance to call the library but map instance is only available inside onLoad, I am trying to use the places library whenever the center change(inside onCenterChange).
import React, { useEffect, useState, useCallback } from 'react';
import { GoogleMap, useJsApiLoader } from '#react-google-maps/api';
import GoogleMapReact from 'google-map-react';
import List from './List'
export default function Nearby(){
const { isLoaded, loadError } = useJsApiLoader({
googleMapsApiKey: "My_Key"
})
const onLoad = useCallback(
function onLoad (map) {
var loc= new window.google.maps.LatLng(6.9270786, 79.861243);
var request = {
location: loc,
radius: '500',
type: ['hospital'],
};
function callback(results, status) {
if (status === window.google.maps.places.PlacesServiceStatus.OK) {
console.log(results)
}
}
let service = new window.google.maps.places.PlacesService(map);
service.nearbySearch(request,callback)
}
)
function onCenterChanged(){
//Need to use service.nearbySearch(request,callback) here
}
return(
<div className='map-container'>
<div className = 'google-map'>
<GoogleMap mapContainerStyle={{ height: '91vh', width: '75vw' }}
zoom={14}
onLoad={onLoad}
center= { currentPos}
onCenterChanged={onCenterChanged()}
>
</GoogleMap>
</div>
</div>
)
}