Error: self-signed certificate in certificate chain

Import { drizzle } from "drizzle-orm/node-postgres";
import { Client } from "pg";
import * as schema from "./schema";
import fs from "fs";
export const client = new Client({
  user: process.env.DB_USER,
  host: process.env.DB_HOST,
  database: process.env.DB_NAME,
  password: process.env.DB_PASSWORD,
  port: parseInt(process.env.DB_PORT || "5432"),
  ssl: {
    rejectUnauthorized: false,
    ca: fs.readFileSync("certificates/global-bundle.pem").toString(),
  },
});
client.connect();

export const db = drizzle(client, { schema });

import { config } from "dotenv";
import { defineConfig } from "drizzle-kit";

config({ path: ".env" });

export default defineConfig({
  schema: "./src/db/schema.ts",
  out: "./migrations",
  dialect: "postgresql",
  dbCredentials: {
    database: process.env.DATABASE!,
    host: process.env.DB_HOST!,
    port: parseInt(process.env.DB_PORT!, 10),
    user: process.env.DB_USER!,
    password: process.env.DB_PASSWORD!,
    ssl: true,
  },
});