NestJS - How to access post body using @Body() decorator?

Kamil Mysliwiec's comment about Content-Type was the solution.

Also, keep in mind to set Content-Type request header into application/json.

In case anyone stumbles on my problem.I had this issue too, but for me was it in the server setup in the main.ts.

I set this code to include a ssl certificate to work with https, but only in production

let serverOptions = null;if (environment.production) {    const httpsOptions = {        key: fs.readFileSync(environment.sslKeyPath),        cert: fs.readFileSync(environment.sslCertPath),    };    serverOptions = { httpsOptions };}const app = await NestFactory.create(AppModule, serverOptions)

but apparently creating a server with options null, will break it.

So I changed it to something like this, since it works with undefined

const app = await NestFactory.create(AppModule, serverOptions ?? undefinded)

alternatively do something like this, cause I don't know if setting the options to undefined is safe

const app = serverOptions ? await NestFactory.create(AppModule, serverOptions) : await NestFactory.create(AppModule)

Hope this helps someone with a similar problem