Could not find a production build in the '/app/.next' directory. Try building your app with 'next build' before starting the production server – Docker

Getting their error while running the next.js app image
:

ready – started server on 0.0.0.0:3000, url: http://localhost:3000

Error: Could not find a production build in the ‘/app/.next’ directory. Try building your app with ‘next build’ before starting the production server. https://nextjs.org/docs/messages/production-start-no-build-id
at NextNodeServer.getBuildId (/app/node_modules/next/dist/server/next-server.js:137:23)
at new Server (/app/node_modules/next/dist/server/base-server.js:93:29)
at new NextNodeServer (/app/node_modules/next/dist/server/next-server.js:86:9)
at NextServer.createServer (/app/node_modules/next/dist/server/next.js:109:16)
at async /app/node_modules/next/dist/server/next.js:121:31
npm ERR! code ELIFECYCLE
npm ERR! errno 1
npm ERR! [email protected] start: next start
npm ERR! Exit status 1
npm ERR!
npm ERR! Failed at the [email protected] start script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output above.
npm ERR! A complete log of this run can be found in:
npm ERR! /root/.npm/_logs/2022-05-11T12_32_58_222Z-debug.log

Dockerfile:

FROM node:14-alpine AS deps
WORKDIR /app

COPY package.json ./
RUN npm install
COPY . .



FROM node:14-alpine AS builder
WORKDIR /app
COPY --from=deps /app ./
RUN npm build


FROM node:14-alpine AS runner
WORKDIR /app

COPY --from=builder /app/package*.json ./
COPY --from=builder /app/public ./public
COPY --from=builder /app/.next ./.next
RUN npm install next

EXPOSE 3000
CMD ["npm","run","start"]

Do I need to add .next in dockerignore? doing so gives me an error while building the image