File 'd:/Courses/React/TEST-2/api-frontend/src/api.d.ts' is not a module.ts(2306)

I am trying to implement my api into my webpage so i can use this frontend as interface to access the api.

I have created files namely api.js for the api:

// src/api.js
import axios from 'axios';

const api = axios.create({
  baseURL: 'http://localhost:8080', // Your API's base URL
  headers: {
    'Content-Type': 'application/json',
  },
});

export const getAllCustomers = () => api.get('/customers');
// Add other API functions as needed

api.d.ts for the module:

// src/api.d.ts
interface Customer {
    id: number;
    firstName: string;
    lastName: string;
    mobileNo: string;
    state: string;
    city: string;
    email: string;  
  }
  
  declare module './api' {
    export function getAllCustomers(): Promise<{ data: Customer[] }>;
    // Add other function declarations as needed
  }
  

server.js:

import express from 'express';
import cors from 'cors';
import api from './api'; // Adjust the path as necessary

const app = express();
const PORT = 8080;

app.use(cors());
app.use(express.json());

app.get('/customers', async (req, res) => {
  try {
    const response = await api.get('/customers'); // Use the API instance
    res.json(response.data); // Forward the API response to the client
  } catch (error) {
    res.status(500).json({ message: 'Error fetching customers', error: error.message });
  }
});

app.listen(PORT, () => {
  console.log(`Server is running on http://localhost:${PORT}`);
});

The file where i want to get all customer details, GetAllCustomerDetails.tsx:

import React, { useEffect, useState } from 'react';
import { getAllCustomers } from '../../api'; 

interface Customer {
  id: number;
  firstName: string;
  lastName: string;
  mobileNo: string;
  state: string;
  city: string;
  email: string;
}

const GetAllCustomerDetails: React.FC = () => {
  const [customers, setCustomers] = useState<Customer[]>([]);
  const [loading, setLoading] = useState<boolean>(true);
  const [error, setError] = useState<string | null>(null);

  useEffect(() => {
    const fetchCustomers = async () => {
      try {
        const response = await getAllCustomers();
        setCustomers(response.data);
      } catch (error) {
        setError("Error fetching customer details");
      } finally {
        setLoading(false);
      }
    };

    fetchCustomers();
  }, []);

  if (loading) {
    return <div>Loading...</div>;
  }

  if (error) {
    return <div>{error}</div>;
  }

  return (
    <div>
      <h2>All Customers</h2>
      <ul>
        {customers.map((customer) => (
          <li key={customer.id}>
            <p>First Name: {customer.firstName}</p>
            <p>Last Name: {customer.lastName}</p>
            <p>Mobile No: {customer.mobileNo}</p>
            <p>State: {customer.state}</p>
            <p>City: {customer.city}</p>
            <p>Email: {customer.email}</p>
          </li>
        ))}
      </ul>
    </div>
  );
};

export default GetAllCustomerDetails;

I am getting an error in importing the api in the GetAllCustomerDetails.tsx file.

The error is :

File 'd:/Courses/React/TEST-2/api-frontend/src/api.d.ts' is not a module.ts(2306)

This is my tsconfig.app.json and tsconfig.node.json respectively:

{
  "compilerOptions": {
    "composite": true,
    "tsBuildInfoFile": "./node_modules/.tmp/tsconfig.app.tsbuildinfo",
    "target": "ES2015",
    "useDefineForClassFields": true,
    "lib": ["ES2020", "DOM", "DOM.Iterable"],
    "module": "ES6",
    "skipLibCheck": true,

    /* Bundler mode */
    "moduleResolution": "bundler",
    "allowImportingTsExtensions": true,
    "resolveJsonModule": true,
    "isolatedModules": true,
    "moduleDetection": "force",
    "noEmit": true,
    "jsx": "react",
    "esModuleInterop": true,
    "forceConsistentCasingInFileNames": true,
    "baseUrl": "src",
    "paths": {
      "*": ["*"]
    },

    /* Linting */
    "strict": true,
    "noUnusedLocals": true,
    "noUnusedParameters": true,
    "noFallthroughCasesInSwitch": true
  },
  "include": ["src/**/*"]
}

{
  "compilerOptions": {
    "composite": true,
    "tsBuildInfoFile": "./node_modules/.tmp/tsconfig.node.tsbuildinfo",
    "skipLibCheck": true,
    "module": "ESNext",
    "moduleResolution": "bundler",
    "allowSyntheticDefaultImports": true,
    "strict": true,
    "noEmit": true
  },
  "include": ["vite.config.ts"]
}

I have tried to change the module to commonjs and the target to es6, but the error is not getting resolved.