データベースを作成できない（MySQL）

MySQLをインストールし、"rails db:create"でデータベースを作成しようとしたところ、以下のエラーが発生しました。
エラー文を検索してみたのですが、あまり有力なものが見つからず困っています。
どなたかヒントでもよろしいのでご教示いただけますでしょうか。
環境は以下になっています。
windows
WSL ubuntu
ruby
ruby on rails
mysql

MySQL
1/home/olivemochi/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/railties-6.0.2.2/lib/rails/app_loader.rb:53: warning: Insecure world writable dir /home/olivemochi/.rbenv/versions/2.5.1 in PATH, mode 040777
2Mysql2::Error::ConnectionError: Access denied for user 'olivemochi'@'localhost' to database 'testapp_development'
3Couldn't create 'testapp_development' database. Please check your configuration.
4rails aborted!
5ActiveRecord::StatementInvalid: Mysql2::Error::ConnectionError: Access denied for user 'olivemochi'@'localhost' to database 'testapp_development'
6/home/olivemochi/testapp/bin/rails:9:in `<top (required)>'
7/home/olivemochi/testapp/bin/spring:15:in `<top (required)>'
8bin/rails:3:in `load'
9bin/rails:3:in `<main>'
10
11Caused by:
12Mysql2::Error::ConnectionError: Access denied for user 'olivemochi'@'localhost' to database 'testapp_development'
13/home/olivemochi/testapp/bin/rails:9:in `<top (required)>'
14/home/olivemochi/testapp/bin/spring:15:in `<top (required)>'
15bin/rails:3:in `load'
16bin/rails:3:in `<main>'
17Tasks: TOP => db:create
18(See full trace by running task with --trace)

以下はconfig/database.ymlの中身です。

yml
1# MySQL. Versions 5.5.8 and up are supported.
2#
3# Install the MySQL driver
4#   gem install mysql2
5#
6# Ensure the MySQL gem is defined in your Gemfile
7#   gem 'mysql2'
8#
9# And be sure to use new-style password hashing:
10#   https://dev.mysql.com/doc/refman/5.7/en/password-hashing.html
11#
12default: &default
13  adapter: mysql2
14  encoding: utf8mb4
15  pool: <%= ENV.fetch("RAILS_MAX_THREADS") { 5 } %>
16  username: olivemochi
17  password: "伏字にしておきます"
18  socket: /var/run/mysqld/mysqld.sock
19
20development:
21  <<: *default
22  database: testapp_development
23
24# Warning: The database defined as "test" will be erased and
25# re-generated from your development database when you run "rake".
26# Do not set this db to the same as development or production.
27test:
28  <<: *default
29  database: testapp_test
30
31# As with config/credentials.yml, you never want to store sensitive information,
32# like your database password, in your source code. If your source code is
33# ever seen by anyone, they now have access to your database.
34#
35# Instead, provide the password as a unix environment variable when you boot
36# the app. Read https://guides.rubyonrails.org/configuring.html#configuring-a-database
37# for a full rundown on how to provide these environment variables in a
38# production deployment.
39#
40# On Heroku and other platform providers, you may have a full connection URL
41# available as an environment variable. For example:
42#
43#   DATABASE_URL="mysql2://myuser:mypass@localhost/somedatabase"
44#
45# You can use this database configuration with:
46#
47#   production:
48#     url: <%= ENV['DATABASE_URL'] %>
49#
50production:
51  <<: *default
52  database: testapp_production
53  username: testapp
54  password: <%= ENV['TESTAPP_DATABASE_PASSWORD'] %>