ActiveRecord looses Entity Value while Writing in Database

hello, trying out the tutorial #250 Authentication from Scratch - RailsCasts gave problems with Ruby 3.1.2p20 and Rails 7.0.3.1. Saving the user entity will make the attribut email nil. In Rails Console the behavior is the same. How can i fix it?


RAILS LOG

Started POST "/users" for ::1 at 2022-08-02 11:28:08 +0200
Processing by UsersController#create as HTML
  Parameters: {"authenticity_token"=>"[FILTERED]", "user"=>{"email"=>"[email protected]", "password"=>"[FILTERED]", "password_confirmation"=>"[FILTERED]"}, "commit"=>"Create User"}
  TRANSACTION (0.0ms)  begin transaction
  ↳ app/controllers/users_controller.rb:9:in `create'
  User Create (0.2ms)  INSERT INTO "users" ("email", "password_hash", "password_salt", "created_at", "updated_at") VALUES (?, ?, ?, ?, ?)  [["email", nil], ["password_hash", "[FILTERED]"], ["password_salt", "[FILTERED]"], ["created_at", "2022-08-02 09:28:08.368729"], ["updated_at", "2022-08-02 09:28:08.368729"]]
  ↳ app/controllers/users_controller.rb:9:in `create'
  TRANSACTION (0.8ms)  commit transaction


Rails Console Log

irb(main):011:0> user = User.find(8)
  User Load (0.1ms)  SELECT "users".* FROM "users" WHERE "users"."id" = ? LIMIT ?  [["id", 8], ["LIMIT", 1]]                                                                     
=>                                                                     
#<User:0x0000000107fac370                                              
...                                                                    
irb(main):012:0> user.email = "[email protected]"
=> "[email protected]"
irb(main):013:0> user.save
=> true
irb(main):014:0> user
=>
#<User:0x0000000107fac370                                              
 id: 8,                                                                
 email: nil,                                                           
 password_hash: "[FILTERED]",                                          
 password_salt: "[FILTERED]",                                   
 created_at: Tue, 02 Aug 2022 08:35:16.377741000 UTC +00:00,    
 updated_at: Tue, 02 Aug 2022 08:35:16.622582000 UTC +00:00>    
irb(main):015:0>