'Prisma ORM Postgres SQL DB Schema Not Null Fields

Just so you have it here is my defined prisma schema.

Now if I read correctly in the prisma docs it said, that every field in which I do not declare a ? after the type, it should be presented as not null, in a relational database.

// This is your Prisma schema file,
// learn more about it in the docs: https://pris.ly/d/prisma-schema

generator client {
  provider = "prisma-client-js"
}

datasource db {
  provider = "postgresql"
  url      = env("DATABASE_URL")
}

model Users {
  id          String      @id @default(uuid())
  createdAt   DateTime    @default(now())
  updatedAt   DateTime    @updatedAt
  email       String      @unique
  password    String
  role        Roles       @default(USER)
  contact     Contacts?   @relation(fields: [contactId], references: [id])
  contactId   String?
}

enum Roles {
  USER
  ADMIN
}

model Contacts {
  id          String    @id @default(uuid())
  createdAt   DateTime  @default(now())
  updatedAt   DateTime  @updatedAt
  firstName   String
  lastName    String
  email       String    @unique
  phone       String
  addressLine String
  city        String
  zipCode     Int
  note        String
  Users       Users?
  events      ContactsOnEvents[]  @relation(name: "guest")
  guests      ContactsOnEvents[]  @relation(name: "guestfrom")
}

model Events {
  id          String      @id @default(uuid())
  createdAt   DateTime    @default(now())
  updatedAt   DateTime    @updatedAt
  name        String
  startDate   DateTime
  EndDate     DateTime
  type        EventTypes  @default(HUNT)
  contacts    ContactsOnEvents[]
}

enum EventTypes {
  HUNT
  EVENT
}

model ContactsOnEvents {
  guest       Contacts  @relation(fields: [guestId], references: [id], name: "guest")
  guestId     String
  guestFrom   Contacts  @relation(fields: [guestFromId], references: [id], name:"guestfrom")
  guestFromId String
  event       Events    @relation(fields: [eventId], references: [id])
  eventId     String
  assignedAt  DateTime  @default(now())
  type        Types[]   

  @@id([guestId, eventId])
}


enum Types {
  HUNTER
  DRIVER
  SEEKER
}

So in this schema I think most of the fields should be not null fields, but when I open it in Prisma studio most of my fields are nullable, ist that some sort of config Error or is it another wierd bug.

For Refrence here a picture of my user table where every field except the contact relation should not be null. Instead all Fields are nullable here cause required fields should be red.